A :) is the correct anwser
Write as a function equation: where f(x) is the same as "y"
f(x) = 5 + 1x ------ y = 1x + 5
Use: y = mx + b (Where m = slope and b is y intercept)
Slope is 1 and y intercept is +5
Remember slope is rise over run so 1 can be written as 1 / 1 and interpreted as rise 1 and run 1 both in the positive direction.
Answer
Let f(x) = ax + b
Then
f(x + 1) = a(x + 1) + b
= ax + a + b
Hence, a = 3, and a + b = 5, b = 2
f(-2) = 3(-2) + 2
= -6 + 2
= - 4
f(2x) = 3(2x ) + 2
= 6x + 2
2 weeks, because the first week the second plant will grow to 6 inches and the first plant will grow to 7, the next week the first plant will be 8 inches and so will the second plant.