Question

Which is the equation of the line with a slope of 2 that goes through the point (1,2.5)

Answer 1

y - 2.5 = 2(x - 1)

Explanation:

Here given slope is 2 and the point through which the straight line passes is (1, 2.5)

Let the equation be y = mx + c where m and c represent slope and y intercept respectively.

We know the slope, so we input that in our equation

y = 2x + c ------- i

This straight line also passes through (1, 2.5)

Putting the values in place of x and y we get,

2.5 = (2X1) + c

⇒ 2.5 = 2 + c

⇒ c = 2.5 - 2

⇒ c = 0.5

Now, putting value of c in i, we get

y = 2x + 0.5 -------- ii

It can also be written as y - 2.5 = 2(x - 1) ------- iii

this equation and ii are same and you can verify that by simplifying iii, by multiplying 2 and then shifting the -2.5 from LHS to RHS