What is the equation of the line that passes
through the points (3,-1) and (7, 3)?

y = 1x + -4

Equation of a straight line:

y = mx + b (i)

Step by Step Solution:

Step 1: Calculating Slope (m).

m = y2-y1 /x2-x1

m = 3--1 /7-3

m = 4/4

m = 1

Now putting value of m in equation (i)

y = 1x + b (ii)

Step 2: Calculating Y-intercept (b).

Lets choose the first point, (3,-1) for calculating y-intercept:

y = mx + b

-1 = 1(3) + b

-1 = 3 + b

-4 = b

b = -4

Now putting value of b in equation (ii)

y = 1x + -4

according to the triangle sum theorem, all the angles in a triangle must add up to 180 degrees. if we know one angle is already 90, we do 180-90=90. the other 2 angles must add up to 90, exactly.

step-by-step explanation: