Chapter 2
3x + 5 = 17
3x = 12 → x = 4
y = 3x – 1
slope = 3
y = –4x + 8
slope = –4, y-intercept = 8
x + 3 < 10
x < 7
x + y = 10
y = 4
x = 6
5(x – 2) = 20
5x – 10 = 20 → 5x = 30 → x = 6
2x + y = 5
y = –2x + 5
{(1,2), (1,5), (2,7)}
No — x = 1 maps to two outputs.
5x > 20
x > 4
2x + y = 5
2x – y = 1
y = 2
4x – 7 = 2x + 9
4x – 2x = 9 + 7 → 2x = 16 → x = 8
Find the slope between (2, 3) and (6, 11).
(11 – 3) / (6 – 2) = 8/4 = 2
2x + 6 = 0
2x = –6 → x = –3
–2x ≤ 8
x ≥ –4
y = –x + 3
y = 2x – 6
y = 0
2(x + 3) – 5 = x + 10
2x + 6 – 5 = x + 10 → 2x + 1 = x + 10 → x = 9
y = –½x + 4
Slope = –½, y-intercept = 4
Given slope = –3 and passing through (4, 2), write the equation.
y = –3x + 14
3(x – 2) + 4 ≥ 10
x ≥ 4
3x – 6y = 12
x – 2y = 4
infiite solutions
7 – 3(2x – 1) = 4x + 8
2 = 10x → x = 0.2
Write the equation of a line in Ax + By = C form with slope 3 and y-intercept –2.
y = 3x – 2 → –3x + y = –2 (or 3x – y = 2)
4y – 12x = 20
y = 3x + 5
Slope = 3
–1 ≤ 2x – 3 < 9
1 ≤ x < 6
2x + 3y = 7
4x – y = –1
y = 15/7