Answer:
x = 25°
Step-by-step explanation:
2x-10°+2x-10°+100°=180°[sum of angles in a triangle ]
4x+80°=180°
4x=100°
x=25°
It is the first answer choice because a negative times a negative is a positive.
Answer:
4 sqrt(2) - sqrt(70)
Step-by-step explanation:
Simplify the following:
(4 sqrt(14) + 4 sqrt(10)) (3 sqrt(7) - 4 sqrt(5))
Factor 4 out of 4 sqrt(14) + 4 sqrt(10) giving 4 (sqrt(14) + sqrt(10)):
4 (sqrt(14) + sqrt(10)) (3 sqrt(7) - 4 sqrt(5))
(sqrt(10) + sqrt(14)) (3 sqrt(7) - 4 sqrt(5)) = sqrt(10) (-4 sqrt(5)) + sqrt(10)×3 sqrt(7) + sqrt(14) (-4 sqrt(5)) + sqrt(14)×3 sqrt(7) = -20 sqrt(2) + 3 sqrt(70) - 4 sqrt(70) + 21 sqrt(2) = sqrt(2) - sqrt(70):
Answer: 4 sqrt(2) - sqrt(70)
