Question

Error Analysis: George was trying to rearrange the formula below to slope-intercept form, y = mx + b. by

solving for y. Identify her mistake and correct the error.
y + 20 = 2(x +20)
y + 20 = -x +20
PLEASE HELP!

Answer 1

George's mistake would be:

Instead of 2x + 40, she has made - x + 20.

Explanation:

Slope - Intercept Form = y = mx + b

y + 20 = 2(x +20)

y + 20 = 2x + 40

- 20 - 20

----------------------

y = 2x + 20

(Should have been the answer)

BUT,

George's Solving:

y + 20 = 2(x + 20)

y + 20 = -x + 20

George's Mistake would be her miscalculation during her 2nd step. Where instead of distributing 2 to (x + 20), she has changed it to -x + 20, when in reality, it should have been 2x + 40.