SAT Prep Cohort Warm-up #1

Answer explanation

Recognize that (0, 2) is the y-intercept.

Using y = mx + b, the equation would be y = 5x + 2

• The initial cost of renting the boat

• The total number of boats rented

• The total number of hours the boat is rented

• The increase in cost to rent the boat for each additional hour

Answer explanation

Find the slope using the slope formula.

• 6

• 7

• 8

• 9

Answer explanation

Recognize the y-intercept is -2.

Find the rate of change. The y-values are increasing by 6 as the x-values increase by 2.

6/2 = 3

So we can write the function in slope-intercept form:

f(x) = 3x - 2

Now we can find f(3):

f(x) = 3(3) - 2 = 7

• The age, in years, of a typical apple tree when it is planted

• The height, in inches, of a typical apple tree when it is planted

• The number of years it takes a typical apple tree to grow

• The number of inches a typical apple tree grows each year

Answer explanation

Recognize that the equation given to us is in slope-intercept form.

y = 36 + 18x

We know the slope is 18 and the y-intercept is 36.

This question wants us to interpret the meaning of the 36. Think of the y-intercept as the starting height of the tree, or the height of apple tree when it was planted.

• 5

• 9

• 14

• 18

Answer explanation

We know from the graph that f(x) = 1/2 x + 3.

We know the slope of g(x) is four times the slope of f(x). So 4 * 1/2 = 2.

This means the slope of g(x) is 2 and we are told the y-intercept of g(x) is -4.

So g(x) = 2x - 4

Therefore, g(9) = 2(9) - 4 = 14

• It has a negative slope and a positive y-intercept.

• It has a negative slope and a negative y-intercept

• It has a positive slope and a positive y-intercept.

• It has a positive slope and a negative y-intercept.

Answer explanation

In order to correctly identify the slope and y-intercept, we need to get this equation into slope-intercept form.

2y - 3x = -4

2y = 3x - 4

y = 3/2x - 2

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Answer explanation

Get the equation into slope-intercept form (y = mx + b)

y - 5x = -6

y = 5x - 6

You're looking for a line with a y-intercept of -6 and a slope of 5.