Answer: Choice C
y = 180 - 2x
y = 2x
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Explanation:
The first sentence says "Two angles of a triangle are congruent", so let's say x represents each of those congruent angles. The third angle (let's call it y) has twice the measure of each of those x angles. This means y = 2x.
Since y = 2x, the answer must be choice C.
Notice that the three angles x, x and y add to 180 as they are part of a triangle
x+x+y = 180
2x+y = 180
y = 180-2x
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Extra info: because y = 2x and y = 180-2x, we can set the two right hand sides equal to each other. We get the equation 2x = 180-2x and it solves to x = 45. This means y = 90. This is an isosceles right triangle.
