Answer:
Slope is defined as rise over run, which can be expressed as the difference of the y-coordinates divided by the difference of the x-coordinates. If we rise, we are moving vertically, or along the y-axis. If we run, we are moving horizontally, or along the x-axis.
The formula for the slope m of a line given two points (x1, y1) and (x2, y2) that lie on the line is:
m = (y2 - y1)/(x2 - x1)
m = (15 - 5)/(-6 - 4)
m= 10/-10
m = -1
Now, we can use the slope-intercept form of the equation of a line to obtain the equation of the line that satisfies the conditions outlined in the problem. Slope-intercept form is:
y = mx + b
Again, m represents the slope, while b stands for the y-intercept. We can use either point on the line to represent x and y. Let's choose the point (4, 5)
5 = -1(4) + b
5 = -4 + b
9 = b
The equation of the line is:
y = -x + 9
Eight *(a number) plus 5*(another number) is -13.
translates to:
8(x) + 5(y) = -13
The sum of (the number) and (the other number) is 1.
translates to:
(x) + (y) = 1
We have a system of two equations involving two unknowns: x and y.

We can easily solve the system using Substitution or Elimination. Let's use Elimination this time.
We'll multiply the second equation by -8 so that the x's match up.

When we add the equations together, the x's will fall out of the equation, summing to zero. The 5y and -8y will sum to -3y and the right hand side will sum to -21.

Divide by -3,

Plug back into one of your original equations to find the value of x,

Subtract 7,
When you subtract and add what is in the parentheses you would get -15 so I’m guessing he didn’t go from left to right when working inside the parentheses but when you solve the whole problem out you would get the answer: -41.25 If I missed something or you need me to show the work just let me know but I hope this helps !