Question

Which linear function represents the line given by the point-slope equation

y – 8 = 1/2(x – 4)?



f(x) =1/2 x + 4

f(x) =1/2 x + 6

f(x) = 1/2x – 10

f(x) =1/2 x – 12

Answer 1

Rewrite the given y – 8 = 1/2(x – 4), replacing "y" with "f(x)."

Then f(x) – 8 = 1/2(x – 4)

Multiply all 3 terms by 2 to eliminate the fraction (1/2):

2f(x) = 16 + x - 4

Combine like terms: 2f(x) = x + 12

x + 12

Divide both sides by 2: f(x) = -----------

2

Note that this is equivalent to f(x) = (1/2)x + 6. Important: Use parentheses as indicated.