Step-by-step explanation:
Select all of the following that are quadratic equations.
x² + 3x - 5 = 0 ✓
x² - x = 3x + 7 ✓
5x - 7 = 0 X
7x² + 14x = 0 ✓
x³ - 3x² + 1 = 0 X
x - 5 = 9x + 7 X
What is quadratic equations?
Quadratic equations is a equation that has a general form like "ax² + bx = c"
For example :
x² + 3x - 5 = 0
x² + 3x = 5
x² → ax²
3x → bx
5 → c
Answer:
The tax amount is 15.17$
The tax rate is 12.4%.
Step-by-step explanation:
First we subtract the cost from the selling price.
137.17 - 122 = 15.17
We have found the tax amount, now for the tax rate.
If tax rate is x, then
122 * x = 137.17
Divide both sides by 122 to get
x = 137.17/122 = 1.124, or .124.
Then convert into percentage by moving the decimal to the right 2 times.
.124 = 12.4%
Hope this helps you
Answer:
no writting shown but
Step-by-step explanation:
i guess its super cool encouragement is the most
Step-by-step explanation:
3/4x + 5/8 = 4x/1
5/8 = 4x/1 - 3/4x
5/8 = 16x^2 - 3/4x
5/8 = 4x - 3/1
5/8 = 4x - 3
Cross multiply
8(4x - 3) = 5
32x - 24 = 5
32x = 5 + 24
32x = 29
X = 29/32
E^2x -2e^x -8=0 => e<span>^(2x) -2e^x -8=0
Temporarily replace e^x with y.
Then (y)^2 - 2y - 8 = 0. Factors are (y-4) and (y+2).
Roots are y = 4 and y= -2.
Now remembering that we temporarily replaced e^x with y, we let
y=4 = e^x. We need to solve for x. Taking the natural log of both sides, we get:
ln 4 = x (answer)
We have to discard the other root (y= -2), because we cannot take the ln of a negative number.
</span>
