21.
So to solve for the value of a variable in an equation, you would need to isolate x on one side. The first thing you have to do is multiply 2 and (x + 7) together, which can be rewritten as 2(x) + 2(7). After multiplying, your equation would be:
, or A.
22.
So the rule with multiplying exponents with the same base is to add the exponents together, and the rule with dividing exponents with the same base is to subtract the exponents. Your equation will be simplified as such:

Now the rule with converting negative exponents into fractions is
. In this case, 4^-2 would turn into
, or C, which is your final answer.
Answer:
$2.47
Step-by-step explanation:
Pretend if Mr. Yasin didn't pay for the 3rd box, find out how much he had left after paying for the first 2 boxes.
9.43 - 3.99 - 2.97 = 2.47
1. Find the greatest common factor (GCF)
What is the largest number that divides evenly into 4x^2, -16x^4, and 10x^5?
It is 2.
What is the highest degree of x that divides evenly into 4x^2, -16x^4, and 10x^5?
It is x^2.
Multiply the results above, the GCF = 2x^2
2. Factor out the GCF (Write the GCF first. Then, in parentheses, divide each term by the GCF.)
2x^2(4x^2/2x^2 + -16x^4/2x^2 + 10x^5/2x^2)
3. Simplify each term in parentheses
2x(2-8x^2+5x^3)
Have a nice day :D