Answer: choice B, 40.5 degrees
The triangle is isosceles based on the fact that AC = BC (the tick marks are the same). The angles opposite the congruent sides are also congruent
angle A = angle B = x for some unknown number x
The three angles A,B,C add to 180, so,
A+B+C = 180
x+x+99 = 180
2x+99 = 180
2x = 180-99
2x = 81
x = 81/2
x = 40.5
So angle A and angle B are both 40.5 degrees
Check:
A+B+C = 180
40.5+40.5+99 = 180
180 = 180 answer is confirmed
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Edit
The sides with the two tick marks are the same length, so 7x-4 is the same as length as 31
7x-4 = 31
7x = 31+4
7x = 35
x = 35/7
x = 5
Answer is choice B) 5
Answer:
3m - 5
Step-by-step explanation:
3(m - 3) + 4 Distribute the 3
3m - 9 + 4 Simplify
3m - 5
Simplifying
5x + 2(8x + -9) = 3(x + 4) + -5(2x + 7)
Reorder the terms:
5x + 2(-9 + 8x) = 3(x + 4) + -5(2x + 7)
5x + (-9 * 2 + 8x * 2) = 3(x + 4) + -5(2x + 7)
5x + (-18 + 16x) = 3(x + 4) + -5(2x + 7)
Reorder the terms:
-18 + 5x + 16x = 3(x + 4) + -5(2x + 7)
Combine like terms: 5x + 16x = 21x
-18 + 21x = 3(x + 4) + -5(2x + 7)
Reorder the terms:
-18 + 21x = 3(4 + x) + -5(2x + 7)
-18 + 21x = (4 * 3 + x * 3) + -5(2x + 7)
-18 + 21x = (12 + 3x) + -5(2x + 7)
Reorder the terms:
-18 + 21x = 12 + 3x + -5(7 + 2x)
-18 + 21x = 12 + 3x + (7 * -5 + 2x * -5)
-18 + 21x = 12 + 3x + (-35 + -10x)
Reorder the terms:
-18 + 21x = 12 + -35 + 3x + -10x
Combine like terms: 12 + -35 = -23
-18 + 21x = -23 + 3x + -10x
Combine like terms: 3x + -10x = -7x
-18 + 21x = -23 + -7x
Solving
-18 + 21x = -23 + -7x
Solving for variable 'x'.
Move all terms containing x to the left, all other terms to the right.
Add '7x' to each side of the equation.
-18 + 21x + 7x = -23 + -7x + 7x
Combine like terms: 21x + 7x = 28x
-18 + 28x = -23 + -7x + 7x
Combine like terms: -7x + 7x = 0
-18 + 28x = -23 + 0
-18 + 28x = -23
Add '18' to each side of the equation.
-18 + 18 + 28x = -23 + 18
Combine like terms: -18 + 18 = 0
0 + 28x = -23 + 18
28x = -23 + 18
Combine like terms: -23 + 18 = -5
28x = -5
Divide each side by '28'.
x = -0.1785714286
Simplifying
x = -0.1785714286
The last two options are correct, but it looks like you’ve got them :)