WRITE LINEAR EQUATIONS IN SLOPE- INTERCEPT FORM December 2, 2013 Pages
y -intercept ANSWER slope ANSWER Copy and complete the statement. ? In the equation y = mx + b, the value of m is the of the graph of the equation. 1. ? In the equation y = mx + b, the value of b is the of the graph of the equation. 2. parallel ANSWER 3. ? Two lines are if their slopes are equal.
Find the slope of the line that passes through the points. ANSWER (4, 5), (2, 3) ANSWER (0, – 6), (8, 0) 6.6. (0, 0), (– 1, 2) ANSWER – 2
Identify the slope and the y- intercept of the line with the equation. 7. y = x y = x – , –6 ANSWER 1, 1 ANSWER 9. y = – 2 5 x– 2 2 5,– 2 ANSWER –
Evaluate the function when x = – 2, 0, and f(x) = x – f(x) = 2x f(x) = – 5x – 7 0, 4, 12 ANSWER 3, – 7, – 27 ANSWER – 12, – 10, – 6 ANSWER
13. Write an equation of the line with a slope of – 2 and a y -intercept of 5. y = mx + b Write slope-intercept form. y = – 2x + 5 Substitute – 2 for m and = for b.
14. Which equation represents the line shown ? The line crosses the y- axis at (0, 3). So, the y- intercept is 3. y = mx + b Write slope-intercept form. 2 y = – x Substitute – for m and 3 for b. 5 = = – The slope of the line is rise run – A y = – x B 5 2 C y = – x D y = 3x + 2 5
15. Write an equation of the line shown in slope-intercept form.
y = mx + b y = x – Substitute for m and 5 for b. 4 3 – STEP 1 Write an equation of the line. The line crosses the y -axis at (0, – 5). So, the y- intercept is – 5. SOLUTION x 2 – x – 0 y 2 – y 1 = m = – 1 – (– 5) = 4 Write slope-intercept form. Calculate the slope. STEP 2
SOLUTION 16. Write an equation for the linear function f with the values f(0) = 5 and f(4) = 17. Calculate the slope of the line that passes through (0, 5) and (4, 17). Write f(0) = 5 as (0, 5) and f (4) = 17 as (4, 17). STEP 1 x 2 – x 1 4 – 0 y 2 – y 1 = m = 17 – 5 = 4 12 = 3 STEP 2
y = mx + b Write slope-intercept form. y = 3x + 5 Substitute 3 for m and 5 for b. Write an equation of the line. The line crosses the y -axis at (0, 5). So, the y- intercept is 5. STEP 3 ANSWER The function is f(x) = 3x + 5.
HOMEWORK Chapter 5, section 1 Pages #4-14, even #18-38, even #53-54, all