Answer:
x = 2
Step-by-step explanation:
x + 3 = -x + 7
Add x to each side
x+x + 3 = -x+x + 7
2x+3 = 7
Subtract 3 from each side
2x = 7-3
2x = 4
Divide by 2
2x/2 = 4/2
x = 2
So Angle GEN and FED are vertical angles, which means that their angles are congruent. Therefore, Angle FED is 60°
Angle GEN and DEN are a linear pair, which means that they are supplementary angles (add up to 180). To find Angle DEN, we have to form the equation: 60 + DEN = 180
For this, all you have to do is subtract 60 on both sides, and your answer will be: DEN = 120°
Answer:eirther C or D not sure
Step-by-step explanation:
Let the three gp be a, ar and ar^2
a + ar + ar^2 = 21 => a(1 + r + r^2) = 21 . . . (1)
a^2 + a^2r^2 + a^2r^4 = 189 => a^2(1 + r^2 + r^4) = 189 . . . (2)
squaring (1) gives
a^2(1 + r + r^2)^2 = 441 . . . (3)
(3) ÷ (2) => (1 + r + r^2)^2 / (1 + r^2 + r^4) = 441/189 = 7/3
3(1 + r + r^2)^2 = 7(1 + r^2 + r^4)
3(r^4 + 2r^3 + 3r^2 + 2r + 1) = 7(1 + r^2 + r^4)
3r^4 + 6r^3 + 9r^2 + 6r + 3 = 7 + 7r^2 + 7r^4
4r^4 - 6r^3 - 2r^2 - 6r + 4 = 0
r = 1/2 or r = 2
From (1), a = 21/(1 + r + r^2)
When r = 2:
a = 21/(1 + 2 + 4) = 21/7 = 3
Therefore, the numbers are 3, 6 and 12.
F(180) = x/30
= 180/30 = 6 gallons of gas is needed
