Answer:
x=4
y=2
Step-by-step explanation:
2x+2y=12
x−y=2
In order to solve by elimination, coefficients of one of the variables must be the same in both equations so that the variable will cancel out when one equation is subtracted from the other.
2x+2y=12,x−y=2
To make 2x and x equal, multiply all terms on each side of the first equation by 1 and all terms on each side of the second by 2.
2x+2y=12,2x+2(−1)y=2×2
Simplify.
2x+2y=12,2x−2y=4
Subtract 2x−2y=4 from 2x+2y=12 by subtracting like terms on each side of the equal sign.
2x−2x+2y+2y=12−4
Add 2x to −2x. Terms 2x and −2x cancel out, leaving an equation with only one variable that can be solved.
2y+2y=12−4
Add 2y to 2y.
4y=12−4
Add 12 to −4.
4y=8
Divide both sides by 4.
y=2
Substitute 2 for y in x−y=2. Because the resulting equation contains only one variable, you can solve for x directly.
x−2=2
Add 2 to both sides of the equation.
x=4
The system is now solved.
x=4,y=2
Correct choice is B) x=4.
3x * 3x = 9x
9x + 6 - 2x + 5x - 4x^2 + 9
9x + 6 - 7x - 4x * 4x + 9
9x + 6 - 7x - 16x + 9
9x + -7x = 2x + 6 - 16x + 9
2x + 6 - 16x + 9
2x + (-3) - 16x
-14x + (-3) is the expression?
Answer:
Step-by-step explanation:
It's already in a form that only ha positive exponents. Just to state it though you could rewrite it as 
or 
The question asks for positive exponents though so yu don't need to do that.
You also need to know 
so in this case 
so 
Answer:
1.A. 88.89
2.B.6.3%
3.C.64.92%
Step-by-step explanation:
1.
to covert it into percentage multiply it with 100
then it becomes 88.888
rounding off to the nearest hundred it becomes 88.89
2. to convert into percentage multiply it with 100
therefore 0.063×100=6.3%
3. to find percentage
%= (no of students using mobile / total no of students )× 100
= 
×100
=64.918
Rounding off to nearest hundred it becomes 64.92%
