so, x =

and y =

Hence, the answer is the first one.
Bu using Pythagoras theorem
(x^2)+(21)^2=(75)^2
Therefore. 5625-441=(x)^2
X^2=5184
Therefore x=72
Third side length=72 units
Answer:
28
Step-by-step explanation:
x = 2 point questions, y = 3 point questions
x + y = 40
2x + 3y = 92
Solving this we get x = 28, y = 12 so the answer is 28.
Answer:
x=6, x=-5
Step-by-step explanation:
Factoring this quadratic gets you (x-6)(x+5)=0, for this to be possible, either x-6 or x+5 has to be zero, so therefor x is 6, or x is -5
Answer:800
Step-by-step explanation:
dont know