Below are two different functions, f(x) and g(x). What can be determined about their slopes? f(x)= 4x + 2 The function g(x) going through 0, −2 and 1, 3 The function f(x) has a larger slope. The function g(x) has a larger slope. They both have the

Below are two different functions, f(x) and g(x)f(x)andg(x). What can be determined about their slopes?

f(x)= 4x + 2f(x)=4x+2 The function g(x)g(x) going through (x,y)=(0, −2) and (x,y)=(1, 3)(x,y)=(0,2)and(x,y)=(1,3)

The function f(x)f(x) has a larger slope.
The function g(x)g(x) has a larger slope.
They both have the same slope.
The relationship between slopes cannot be determined.

2 Answers
Jun 23, 2018

f(x)=4x+2f(x)=4x+2, g(x)=5x-2g(x)=5x2
Therefore g(x)g(x) has a larger slope.

Explanation:

The slope is the constant in front of x, i.e. f(x) has a slope of 4

The way I understand your statement, you mean that g(x) goes through the points (0, -2) and (1, 3) (otherwise one might understand your statement that g(x) is, 0, -2, 1, 3 for some values of x).
(Please remember to write precisely what you are asking, otherwise you risk misunderstanding of your question.)

From this it follows that g(0)=-2g(0)=2 and g(1)=3g(1)=3,
i.e. g(x)g(x) increases (has a slope of) 3+2=53+2=5 when x increases fro 0 to 1.

Therefore g(x) has a greater slope than f(x).

If we write g(x)=ax+b
we have a*0+b=-2a0+b=2 => b=-2b=2
a*1-2=3a12=3 => a=5a=5
Therefore, g(x)=5x-2g(x)=5x2

Jun 23, 2018

g(x)g(x) has the 'greater' slope

Explanation:

The slope of f(x)f(x) is such that it 'goes up' 4 for 1 along.

Lets have a look at g(x)g(x)

The slope (gradient) is determined by reading along the x-axis from left to right. Thus using xx the left most point P_1->(x_1,y_1)=(0,-2)P1(x1,y1)=(0,2) and the right most point P_2->(x_2,y_2)=(1,3)P2(x2,y2)=(1,3)

For the slope we have

P_2-P_1 = ("change in y")/("change in x") =(y_2-y_1)/(x_2-x_1) = (3-(-2))/(1-0)=5/1=5P2P1=change in ychange in x=y2y1x2x1=3(2)10=51=5

So for the gradient:

g(x)->5g(x)5
f(x)->4f(x)4

Thus g(x)g(x) has the 'greater' slope

Bad practice to use the word 'larger' for a measure of slope