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A line passes through the point (–2, 7) and has a slope of –5. What is the value of a if the point (a, 2) is also on the line?

A.–7
B.–1
C.1
D.7

User IraSenthil
by
8.6k points

2 Answers

1 vote

Answer:

The answer is B.

Explanation:

User Shamsul Haque
by
8.2k points
6 votes

Answer:

The correct option is B.

Explanation:

The slope of a line is constant.

If a line passes through two points then the slope of the line is


m=(y_2-y_1)/(x_2-x_1)

It is given that the line passes through (-2,7) and (a,2).

Using the above formula the slope of the line is


m=(2-7)/(a-(-2))


m=(-5)/(a+2)

It is given that the slope of the line is -5. Substitute m=-5 in the above equation.


-5=(-5)/(a+2)

On cross multiplication we get


-5(a+2)=-5

Divide both sides by -5.


a+2=1

Subtract 2 from both the sides.


a=1-2


a=-1

The value of a is -1. Therefore the correct option is B.

User WackGet
by
7.7k points

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