Answer:
x = 3 or -7
Step-by-step explanation:
Recall that for a quadratic equation in the form:
Ax² + Bx = C
we need to add (B/2)² to both sides of the equation to
In our case, we are given:
x² + 4x = 21
compared to the general equation above, B = 4, hence we need to add (4/2)² to both sides
x² + 4x = 21 (complete the square)
x² + 4x + (4/2)² = 21 + (4/2)²
x² + 4x + 2² = 21 + 2²
(x+ 2)² = 21 + 4
(x+ 2)² = 25 (take square root of both sides)
(x+2) = ±√25
(x+2) = ±5
hence
(x+2) = +5----> x = 5 - 2 = 3 (answer)
or
(x+2) = -5 ----> x = -5 - 2 = -7(answer)
Answer:
Step-by-step explanation:
Answer:
-45
-26x+30
Step-by-step explanation:
So first you let's divide this equation into three parts.
Part one -9x(5x+4)
- Step one: you have to distribute the -9x to the numbers in the parentheses. That would leave us with a -9x*5x = -45
and -9x*4 = -36x - Step two: Put the answers together. That would leave us with -45
-36x.
Part two 10(x+3)
- Step one: you have to distribute the 10 to the numbers in the parentheses. That would leave us with a 10*x = 10x and 10*3 = 30
- Step two: Put the answers together. That would leave us with 10x+30
Part three solve
- Step one: combine and put together what you have solved for. That would leave us with a -45
-36x+ 10x+30 - Step two: combine like terms. The like terms here are -36x and 10x. When you combine them you would get -26x.
- Step three: Write the equation in standard form. Therefore the answer is -45
-26x+30.
Let me know if anything is confusing!
Answer:
x=60 degrees
Step-by-step explanation:
All triangles equal to 180 degrees. 180-30=150-90=60