Answer:


Step-by-step explanation:
Given system of equations:

To solve by the method of substitution, substitute the first equation into the second equation and rearrange so that the equation equals zero:

Factor the quadratic:

Apply the <u>zero-product property</u> and solve for x:


Substitute the found values of x into the <u>second equation</u> and solve for y:


Therefore, the solutions are:


Answer:
The triangle is an isosceles triangle and the measure of the third angle is 120°
Step-by-step explanation:
the other nd 2 angles in the triangle both measures 30 degrees, the triangle angle sum theorem states that all the angles in a triangle add up to 180 degrees. Add the first two angles together and subtract it from 180. That's
180 - 60 and it equals 120
If there are 15 boards there are 14 gaps in-between.
But first, 15 boards each 9 and 1/4th inches so you get a total of 138 inches and 3/4th
If you subtract that from 144 you get 5 inches and 1/4th. The remaining amount is the total of all of the distance from the spacing.
Then you divide that by 14 (number of gaps/spacing in-between.)
So you get .375 inches. (3/8)
So width of the spacing between each board is 3/8ths of a inch
The midpoint between -4 and 8 is answer B) 2