You add two equations together to eliminate a variable. This particular problem is nice, because it's already setup to eliminate X.
3x - 4y = 9
<span>-3x + 2y = 9
</span>
When we add these two together, 3x - 3x cancels each other out, leaving us with 0x, or nothing.
We continue with -4y + 2y (leaves us with -2y) and 9+9 (18).
-2y = 18
18/-2 = -9.
Now we have y = -9, and we can go back into the problems to solve for x.
<span>3x - 4(-9) = 9
</span>
3x + 36 = 9.
3x = -27
x = -9.
Confirm with the final equation:
-3(-9) + 2(-9) = 9
27 - 18 = 9
9 = 9 --- Confirmed.
Answer:
x^2-3x=4
x^2-3x-4=0
x^2-4x+x-4=0
x(x-4)+1(x-4)=0
(x+1)(x-4)=0
x=-1,4
x- intercepts in the point (-1,0) and (4,0)
Step-by-step explanation:
Answer:
x = 15
Explanation:
First, add both equations on one side, and set it equal to 180° because it's supplementary:
2x + 8 + 8x + 22 = 180
combine like terms:
10x + 30 = 180
subtract 30 on both sides of the equation and you end up with:
10x = 150
divide both sides by 10 and you get:
x = 15
5)
Equilateral triangle, all sides are equal
So 2x + 5 = 11
2x = 6
x = 3
Answer is the first one
3; Equilateral theorem
6)
Isosceles triangle has at least two congruent sides.
So 6x = 24
x = 4
Answer x = 4
Converse of the Base Angle Theorem
7)
5x + 7 = 52
5x = 45
x = 9
Answer
x = 9
Base angle theorem
8)
5y - 14 = 3y
2y = 14
y = 7
Answer
7; Equiangular theorem
