Solve by elimination.
The goal is to cancel out one of the variables in order to easily solve for the other variable.
Do this by changing the equations so that the coefficients of either x or y add up to 0.
Notice the coefficients of y are 3 and 3, if we make one of them negative then they add up to 0. 3+ (-3) = 0
Multiply 2nd equation by -1.
6x +3y = 9
-2x -3y = -1
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4x +0y = 8
Solve for x
4x = 8
x = 8/4 = 2
Plug x=2 back into one of original equations to find y.
---> 2(2) + 3y = 1
---> 4 + 3y = 1
---> 3y = -3
---> y = -1
Therefore solution is (2,-1)
Choice C for problem 6 is correct. The two angles (65 and 25) add to 90 degrees, proving they are complementary angles.
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The answer to problem 7 is also choice C and here's why
To find the midpoint, we add up the x coordinates and divide by 2. The two points A(-5,3) and B(3,3) have x coordinates of -5 and 3 respectively. They add to -5+3 = -2 which cuts in half to get -1. This means C has to be the answer as it's the only choice with x = -1 as an x coordinate.
Let's keep going to find the y coordinate of the midpoint. The points A(-5,3) and B(3,3) have y coordinates of y = 3 and y = 3, they add to 3+3 = 6 which cuts in half to get 3. The midpoint has the same y coordinate as the other two points
So that is why the midpoint is (-1,3)
W-13=15 add 13 on both sides to isolate variable and you get w=13+15, w=28
