Answer:
Excluded Value : 3 and -5
Step-by-step explanation:
hello :
Excluded Value : and
the excluded value when : x²+2x-15=0
(
x²+2x+1)-1-15=0
means : (x+1)²-16=0 (x+1)²-4² = 0
by identity : a²-b² =(a-b)(a+b)
(x+1-4)(x+1+4) =0 so : (x-3)(x+5) =0 means : x-3=0 or x+5=0
x=3 or x= -5
Excluded Value : 3 and -5
His average is 80%. You take the two scores add them up and divide by the number of scores.
Answer:
-17
Step-by-step explanation:
8x -2y= 12
<em>Divide</em><em> </em><em>the</em><em> </em><em>whole</em><em> </em><em>equation</em><em> </em><em>by</em><em> </em><em>2</em><em>:</em>
4x -y= 6
<em>Rewrite the equation into the slope-intercept form (y=mx+c, where m is the gradient while c is the y-intercept).</em>
-y= -4x +6
y= 4x -6
Thus, gradient of given line= 4.
Since parallel lines have the same gradient, gradient of line= 4.
y= 4x +c
<em>To find the y-intercept of the lone, substitute a pair of coordinates.</em>
When x=5, y=3,
3= 4(5) +c
3= 20 +c
c= 3 -20
c= -17
Thus, the y-intercept of the line is -17.
Answer: $130.50
Step-by-step explanation:
2.5 hours= $25 an hour
25+25+12.50=$62.50
Muffler=$65
65plus62.50
Total= $130.50
The first step is to identify the order in which the equation must be solved, by following PEMDAS (you might know it as BEDMAS):
Parenthesis (or Brackets)
Exponents
Multiplication and Division
Addition and Subtraction
My advice would be to add parenthesis, following these rules, if you are not very good at finding them immediately by sight.
So:
![4 - 5 / 2 * (\frac{1}{10x}) = 1\\\\4 - [(5/2)*(\frac{1}{10x})]=1\\\\4-(2.5*\frac{1}{10x})=1\\\\4-\frac{2.5}{10x}-1=0\\3-\frac{x}{4}=0\\\frac{x}{4}=3\\x=3*4\\x=12](https://tex.z-dn.net/?f=4%20-%205%20%2F%202%20%2A%20%28%5Cfrac%7B1%7D%7B10x%7D%29%20%20%3D%201%5C%5C%5C%5C4%20-%20%5B%285%2F2%29%2A%28%5Cfrac%7B1%7D%7B10x%7D%29%5D%3D1%5C%5C%5C%5C4-%282.5%2A%5Cfrac%7B1%7D%7B10x%7D%29%3D1%5C%5C%5C%5C4-%5Cfrac%7B2.5%7D%7B10x%7D-1%3D0%5C%5C3-%5Cfrac%7Bx%7D%7B4%7D%3D0%5C%5C%5Cfrac%7Bx%7D%7B4%7D%3D3%5C%5Cx%3D3%2A4%5C%5Cx%3D12)
We check our answer:
![x=12\\4 - [(5 / 2) * (1/10)*(x)] = 1\\4 - [(5 / 2) * (\frac{1}{10}) * (12))] = 1\\4 - [2.5 * (\frac{1}{10})*12] = 1\\4 - [(\frac{2.5}{10})*12] = 1\\4 - [(\frac{1}{4})*12] = 1\\4 - 3 = 1\\1=1](https://tex.z-dn.net/?f=x%3D12%5C%5C4%20-%20%5B%285%20%2F%202%29%20%2A%20%281%2F10%29%2A%28x%29%5D%20%3D%201%5C%5C4%20-%20%5B%285%20%2F%202%29%20%2A%20%28%5Cfrac%7B1%7D%7B10%7D%29%20%2A%20%2812%29%29%5D%20%3D%201%5C%5C4%20-%20%5B2.5%20%2A%20%28%5Cfrac%7B1%7D%7B10%7D%29%2A12%5D%20%3D%201%5C%5C4%20-%20%5B%28%5Cfrac%7B2.5%7D%7B10%7D%29%2A12%5D%20%3D%201%5C%5C4%20-%20%5B%28%5Cfrac%7B1%7D%7B4%7D%29%2A12%5D%20%3D%201%5C%5C4%20-%203%20%3D%201%5C%5C1%3D1)
We are right!
So, 
.
