Question 389531
I  may be mistaken, but your fist set said -1.1, I assumed it was -1, 1.

Hope this helps:

(-1,1),(7,5)

Use y=mx+b to calculate the equation of the line, where m represents the slope and b represents the y-intercept.
To calculate the equation of the line, use the y=mx+b format.

Slope is equal to the change in y over the change in x, or 'rise over run'.
m=(change  in  y)/(change  in  x)

The change in x is equal to the difference in x-coordinates (also called run), and the change in y is equal to the difference in y-coordinates (also called rise).
m=(y2-y1)/(x2-x1)

Substitute in the values of x and y into the equation to find the slope.
m=(5-(1))/(7-(-1))

Multiply -1 by each term inside the parentheses.
m=(5-(1))/(7+1)

Add 1 to 7 to get 8.
m=(5-(1))/(8)

Multiply -1 by each term inside the parentheses.
m=(5-1)/(8)

Subtract 1 from 5 to get 4.
m=(4)/(8)

Reduce the expression (4)/(8) by removing a factor of 4 from the numerator and denominator.
m=(1)/(2)

Find the value of b using the formula for the equation of a line.
y=mx+b

Substitute the value of m into the equation.
y=((1)/(2))*x+b

Substitute the value of x into the equation.
y=((1)/(2))*(-1)+b

Substitute the value of y into the equation.
(1)=((1)/(2))*(-1)+b

Since b is on the right-hand side of the equation, switch the sides so it is on the left-hand side of the equation.
((1)/(2))*(-1)+b=(1)

Multiply ((1)/(2)) by (-1) to get ((1)/(2))(-1).
((1)/(2))(-1)+b=(1)

Remove the parentheses around the expression 1.
((1)/(2))(-1)+b=1

Multiply (1)/(2) by -1 to get -(1)/(2).
(-(1)/(2))+b=1

Reorder the polynomial -(1)/(2)+b alphabetically from left to right, starting with the highest order term.
b-(1)/(2)=1

Find the value of b.
b=(3)/(2)

Now that the values of m(slope) and b(y-intercept) are known, substitute them into y=mx+b to find the equation of the line.
y=(x)/(2)+(3)/(2)