Inequalities and Identities

14 questions

1.8: Past-paper question 4

4PM1/1/June/2025 — Question 4 · 8 marks

1.8 diagram 1
(a) On the grid opposite, draw the graph of the line with equation
(i)3x+2y=18(ii)x+3y6=0(iii)y=3x(i) \quad 3x + 2y = 18 \quad (ii) \quad x + 3y - 6 = 0 \quad (iii) \quad y = 3x
(3)
(b) Show, by shading on the grid, the region R\displaystyle R defined by the inequalities
3x+2y18x+3y60y3x3x + 2y \leq 18 \quad x + 3y - 6 \geq 0 \quad y \leq 3x
(1)
For all points in R\displaystyle R, with coordinates (x,y)\displaystyle (x, y)
P=2xyP = 2x - y
(c) find the least value of P\displaystyle P
(4)
Only use this grid if you need to redraw your graph.

1.11: Past-paper question 5

4PM1/1/November/2025 — Question 5 · 8 marks

(a) On the grid opposite, draw the line with equation
(i) 3x4y=12\displaystyle 3x - 4y = 12
(ii) y+6+3x=0\displaystyle y + 6 + 3x = 0
(iii) 3y=18x\displaystyle 3y = 18 - x
(3)
(b) Show, by shading on the grid, the region R\displaystyle R defined by the inequalities
3x4y123x - 4y \leq 12
y+6+3x0y + 6 + 3x \geq 0
3y18x3y \leq 18 - x
(1)
For all points in R\displaystyle R, with coordinates (x,y)\displaystyle (x, y)
P=3x2yP = 3x - 2y
Using values from your graph,
(c) find the least value of P\displaystyle P and the greatest value of P\displaystyle P
(4)
Only use this grid if you need to redraw your graph.

1.9: Figure 1 shows a rectangle with width cm and length cm.

4PM1/1R/June/2025 — Question 5 · 7 marks

1.9 diagram 1
(2x+3)cm(2x + 3) \mathrm{cm}
Figure 1 shows a rectangle with width x\displaystyle x cm and length (2x+3)\displaystyle (2x + 3) cm.
The perimeter of the rectangle is P\displaystyle P cm and the area of the rectangle is A\displaystyle Acm2\displaystyle \mathrm{cm}^2
P>10andA<35P > 10 \quad \mathrm{and} \quad A < 35
Find the set of possible values for x\displaystyle x
Give your answer in the form a<x<b\displaystyle a < x < b where a\displaystyle a and b\displaystyle b are rational numbers.
Show clear algebraic working.
(7)

1.10: Find the set of values for for which (a) (b) (c) both and

4PM1/2/June/2025 — Question 2 · 5 marks

Find the set of values for x\displaystyle x for which
(a) 93x>11x+2\displaystyle 9 - 3x > 11x + 2
(1)
(b) 10x2+7x<12\displaystyle 10x^2 + 7x < 12
(3)
(c) both 93x>11x+2\displaystyle 9 - 3x > 11x + 2 and 10x2+7x<12\displaystyle 10x^2 + 7x < 12
(1)

1.6: Past-paper question 1

4PM1/1/November/2024 — Question 1 · 4 marks

(a) On the grid below, draw the line with equation
(i) 3x+4y=24\displaystyle 3x + 4y = 24      (ii) 2x5y+10=0\displaystyle 2x - 5y + 10 = 0
(2)
(b) Show, by shading on the grid, the region R\displaystyle R defined by the inequalities
3x+4y242x5y+100y5x13x + 4y \leq 24 \quad 2x - 5y + 10 \geq 0 \quad y \leq 5 \quad x \geq -1
Label the region R\displaystyle R
(2)

1.7: The length of rectangle is 2 cm greater than its width.

4PM1/2/November/2024 — Question 2 · 6 marks

The length of rectangle R\displaystyle R is 2 cm greater than its width.
The area of R\displaystyle R is greater than 8cm2\displaystyle 8\mathrm{cm}^2 and the perimeter of R\displaystyle R is less than 30cm\displaystyle 30\mathrm{cm}.
Given that the width of R\displaystyle R is w\displaystyle w cm,
find the set of possible values of w\displaystyle w
Give your answer in the form a<w<b\displaystyle a < w < b where a\displaystyle a and b\displaystyle b are rational numbers.
(6)

1.3: Past-paper question 5

4PM1/2/June/2023 — Question 5 · 7 marks

1.3 diagram 1
(a) On the grid opposite draw the line with equation
(i)y=2x+5(ii)4y=x8(iii)5y+3x=30(i) \quad y = 2x + 5 \quad (ii) \quad 4y = x - 8 \quad (iii) \quad 5y + 3x = 30
(3)
(b) Show, by shading, the region R\displaystyle R defined by the inequalities
y2x+54yx85y+3x30y \leq 2x + 5 \quad 4y \geq x - 8 \quad 5y + 3x \leq 30
(1)
For all points in R\displaystyle R with coordinates (x,y)\displaystyle (x, y)
P=2x5yP = 2x - 5y
(c) Using your graph, find the least value of P\displaystyle P
(3)
Only use this grid if you need to redraw your graph.

1.5: Past-paper question 4

4PM1/2/November/2023 — Question 4 · 8 marks

1.5 diagram 1
(a) On the axes opposite, draw the line with equation
(i) y=x1(ii) y=3x+8=0(iii) 2y=x+8\begin{aligned} \text{(i) } y &= -x - 1 & \text{(ii) } y &= -3x + 8 = 0 & \text{(iii) } 2y &= x + 8 \\ & & & &\end{aligned}
(3)
(b) Show, by shading on your graph, the region R\displaystyle R defined by the inequalities
yx1andy3x8and2yx+8y \geq -x - 1 \quad \mathrm{and} \quad y \geq 3x - 8 \quad \mathrm{and} \quad 2y \leq x + 8
(1)
For all points in R\displaystyle R, with coordinates (x,y)\displaystyle (x, y)
P=2y3xP = 2y - 3x
(c) Find
(i) the greatest value of P\displaystyle P
(ii) the least value of P\displaystyle P
(4)
Only use this grid if you need to redraw your graph.

1.4: Find the set of values of for which

4PM1/2R/June/2023 — Question 2 · 6 marks

Find the set of values of x\displaystyle x for which
(a)2(x+1)<5x2(a) 2(x + 1) < 5x - 2
(2)
(b)3x2x10(b) 3x^2 - x \leq 10
(3)
(c)both2(x+1)<5x2and3x2x10(c) \mathrm{both} 2(x + 1) < 5x - 2 \mathrm{and} 3x^2 - x \leq 10
(1)

1.1: Solve and combine inequalities

4PM1/2/June/2021 — Question 1 · 6 marks

Find the set of values of x\displaystyle x for which
(a) 8x7<5x+5,8x-7<5x+5,
(2)
(b) 2x25x3>0,2x^2-5x-3>0,
(3)
(c) both 8x7<5x+5\displaystyle 8x-7<5x+5 and 2x25x3>0\displaystyle 2x^2-5x-3>0.
(1)

1.2: Sketch lines and shade a region

4PM1/1/November/2020 — Question 2 · 4 marks

(a) Using the axes below, sketch the lines with equations
(i) y=6\displaystyle y=6,
(ii) y+x=10\displaystyle y+x=10,
(iii) y=2x5\displaystyle y=2x-5.
Show the coordinates of any point where each line crosses the coordinate axes.
(3)
(b) Show, by shading on your sketch, the region R\displaystyle R defined by the inequalities
y6,y+x10,y2x5,x0.y\leq6, \qquad y+x\leq10, \qquad y\geq2x-5, \qquad x\geq0.
(1)

1.14: 2 (a) Using the axes below, sketch the line with equation (@) y+ 2x=-5 (ii) y=x+4 Show the

4PM1/2/January/2019 — Question 2 · 3 marks

(a) Using the axes below, sketch the lines with equations
(i) y+2x=5\displaystyle y+2x=-5,
(ii) y=x+4\displaystyle y=x+4.
Show the coordinates of the points where each line crosses the coordinate axes.
(2)
(b) Show, by shading, the region R\displaystyle R defined by the inequalities
y+2x>5,y<x+4,x<1.y+2x>-5, \qquad y<x+4, \qquad x<1.
(1)

1.13: Linear Programming on a Graph

4PM1/2R/June/2019 — Question 5 · 7 marks

1.13 diagram 1
(a) On the grid provided, draw the graphs of the lines with equations
2x+3y=24,y=2x,3y=2x12.2x+3y=24, \qquad y=2x, \qquad 3y=2x-12.
(3)
(b) Show, by shading on the grid, the region R\displaystyle R defined by the inequalities
2x+3y24,y2x,3y2x12,y0.2x+3y\leqslant24, \qquad y\leqslant2x, \qquad 3y\geqslant2x-12, \qquad y\geqslant0.
(1)
For all points in R\displaystyle R, with coordinates (x,y)\displaystyle (x,y),
F=2x+5y.F=2x+5y.
(c) Find the greatest value of F\displaystyle F.
(3)