Answer:
You should use MathPapa.
Step-by-step explanation:
Answer:
I might be able to help as long as there's no algebra involved
so you are going to use the Pythagorean theorem on the smaller triangle to find the connecting side's length

now you can find the bigger triangle's hypotenuse

c=4
Answer:
angle 1 and angle 3 are congruent
Step-by-step explanation:
Angles supplementary to the same angle are congruent. Here both angles 1 and 3 are supplementary to angle 2, so angles 1 and 3 are congruent.
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If you like, you can get there algebraically:
m∠1 + m∠2 = 180
m∠3 + m∠2 = 180
Subtract the second equation from the first:
(m∠1 + m∠2) - (m∠3 + m∠2) = (180) - (180)
m∠1 -m∠3 = 0 . . . . simplify
m∠1 = m∠3 . . . . . . add m∠3
When angle measures are the same, the angles are congruent.
∠1 ≅ ∠3