Can someone help me with 8th grade math problems?

- What is \$900 in a account that pays 6% per year. What will the balance be like in 5years?

- Bill purchased a new car for 16,000. The car loses 12 in its value per year. After how many years will it be worth only half of what it was worth when it was purchased?

- Solve -4(x + 2)=2x +10

- What is equivalant to b^6/b^2 (The ^ is to the power sign)

- If 2^4 = 16 and 2^2 = 4, 2^0=1 and 2^-2 = 1/4 what does 2^-4 equal

-what is equivalant to (xy)^-4

If you can, could you please explain how you got these answers.

Relevance
• Anonymous

1) \$900 - [ \$900 * (6/100) x 5 ] = \$468

2) did you mean 12%?

\$8,000 = \$16,000 * 12/100 * years

[\$8,000 / \$16,000] / (12/100) = years

25/6 = years

~4.17= years

3) -4(x + 2)=2x +10

-4x + 8 = 2x + 10

move "like terms" together over the equal sign

-4x - 2x = 10 - 8

-6x = 2

x = -3

4) b^6/b^2 = b^(6-2) = b^4

remember:

rule1: n^a/n^b =n^(a-b)

rule2: (n^a) * (n^b) = n^(a+b)

5) checking with you calculator... 2^4 = 16 right? follow the pattern you see. so... 2^-4 = 1/16

6) (xy)^-4 is equal to the -1/4 root of xy or also equal to 1/xy^4

• Anonymous

I am confused with first two.

3) -4(x + 2) = 2x+10

=> -4x - 8 = 2x + 10

=> -4x -2x = 10 + 8

=> -6x= 18

x = -3

4) b^6-2

=>b^4

5)Since, 2^4 = 16

Thus, 2^-4 = 1/16

6) 1/xy^4

7)

ok Solve -4(x + 2)=2x +10

the answer is x= negative 3

b^6/b^2