Answer:
x = 2±sqrt(11)
Step-by-step explanation:
x^2 -4x - 7 =0
Add 7 to each side
x^2 -4x -7+7 =0+7
x^2 -4x =7
To complete the square take the coefficient of the x term and divide by 2 and then square it. Add it to both sides
-4 /2 = -2 then square
(-2)^2 = 4
Add 4 to both sides
x^2 -4x+4 =7+4
x^2 -4x+4 = 11
Factor the left side into (x-b/2)^2
(x-2)^2 =11
Take the square root of each side
sqrt((x-2)^2) =±sqrt(11)
x-2 = ±sqrt(11)
Add to to each side
x-2+2 = 2±sqrt(11)
x = 2±sqrt(11)
(by 0 i mean the "theta" sign)
cot0 x sec0 = csc0
(cos0/sin0) x (1/cos0) = 1/sin0
1/sin0 = 1/sin
Answer:
x = 3
Step-by-step explanation:
we can use the Pythagorean theorem to solve this problem
x^2 + 4^2 = 5^2
x^2 + 16 = 25
x^2 = 9
x = +/- 3
we take only the positive value because a length can‘t be negative
x = 3
If it is area you're looking for, the answer is 7.92 cm^2, or ~7 11/12 cm^2.
Do you mean 5+7?
If so, that equals 12!
