Answer:
x ≈ - 5.32, x ≈ 1.32
Step-by-step explanation:
Given
x² + 4x - 7 = 0 ( add 7 to both sides )
x² + 4x = 7
To complete the square
add ( half the coefficient of the x- term )² to both sides
x² + 2(2)x + 4 = 7 + 4
(x + 2)² = 11 ( take the square root of both sides )
x + 2 = ±
( subtract 2 from both sides )
x = - 2 ± 
Thus
x = - 2 -
≈ - 5.32 ( to 2 dec. places )
x = - 2 +
≈ 1.32 ( to 2 dec. places )
Start by decomposing the number inside the root into primes
Then group the terms into cubes if possible

rewrite the root
![\sqrt[3]{80}=\sqrt[3]{10\cdot2^3}](https://tex.z-dn.net/?f=%5Csqrt%5B3%5D%7B80%7D%3D%5Csqrt%5B3%5D%7B10%5Ccdot2%5E3%7D)
then cancel the terms that are cubes and bring them out of the root
Alrighty!
*Note the ">" sign is similar to the "=" sign.
3m - 3(3m + 8) > 3m
3m - 6m + 24 > 3m (distribute)
-3m + 24 > 3m (combine like terms)
24 > 6m (Compute/simplify)
8 > m
Makes sense?
Answer:
x = 9/4
Step-by-step explanation:
Locate point G on segment DE so that DG = 1 and GE = 4. CG is parallel to AD, so ΔCGE ~ ΔABC. Corresponding sides are proportional.
AB/BC = CG/GE
x/1 = 9/4
x = 9/4
_____
<em>Additional comment</em>
Using the given triangles, you can write the proportion statement as ...
(9+x)/x = 5/1
We judge this to take more steps to solve, so we prefer the method shown above.
Answer:
y=−2x+4
Step-by-step:
2y+4x=8
Step 1: Add -4x to both sides.
4x+2y+−4x=8+−4x
2y=−4x+8
Step 2: Divide both sides by 2.
2y
/2
=
−4x+8
/2
y=−2x+4