Answer:
- C) (x − 3)2 = 25
- C) Factor out 4 from 4x2 + 40x.
Step-by-step explanation:
1. Adding the square of half the x-coefficient to both sides of the equation will "complete the square." That square is 9, so the result on the right is 16+9 = 25. Only selection C matches.
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2. To complete the square, you want to be able to put the quadratic into the form a(x -h)^2 = -k. For the purpose, it is most convenient to first factor "a" from the given quadratic. Then you can determine "-h" to be half the x-coefficient inside the parentheses.
Here, that looks like ...
4(x² +10x) = 80 . . . . . . . . . . step 1: factor out 4
4(x² +10x +25) = 180 . . . . . add 25 inside parentheses and the same number (4·25) on the right side of the equation
4(x +5)² = 180 . . . . . . . . . . . written as a square
Answer:
Its the first choice: right, scalene.
Step-by-step explanation:
It is a right angled triangle, (indicated by the little square at Q).
The sides have different lengths so it scalene.
5x + 2y = 6
3x + y = 4....multiply by -2
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5x + 2y = 6
-6x - 2y = -8 (result of multiplying by -2)
-------------add
-x = -2
x = 2
5x + 2y = 6
5(2) + 2y = 6
10 + 2y = 6
2y = 6 - 10
2y = -4
y = -4/2
y = -2 <=== here it is
One expression could be three x to the power of two. Let me know if that's right :)