Need Big Help On SUMMER Math Homework!!??

Question

okay i'm going into honors algebra 2 trig. and i had to do summer homework. I'm done with it, but i feel like i did some of it wrong. If you could answer these questions please i will make sure you get the best answer. I promise that i have already done all of these problems, but i'm just not sure if their right. So i will give you the problem and then the answer i got, if i'm right just say so but if i'm not can you do the problem out for me plz!!!: x=variable *=multiply

SIMPLIFY THE EXPRESSION

1) 1/5d 2/7d igot= 17/35d

2) 6h-3h(h+1) igot= -3h^2+9h

3) 9k-2(3k-5)-10 igot= 3k

SOLVE IF POSSIBLE

1) Roger bought some 33cent stamps and some 20cent stamps, and spent $4.50. How many of each type of stamp did he buy?

igot= not enough information to solve

USE SUBSTITIUTION TO SOLVE THE SYSTEM OF LINEAR EQUATIONS.

1) x-.5=6

0.5x 0.2y=8 igot (13.14, 14.29)

SIMPLIFY THE EXPRESSION. THE SIMPLIFIED EXPRESSION SHOULD HAVE NO NEGATIVE EXPONENTS.

1) 2n^4*(3n)^2 igot= 2n^8*9

2) (r/3s)^(-3) {{{ (-3) is an exponent}}}} igot: (3s^3)/r^3

3) w^5* (7/w^4)^2 igot= 49/w^40

4) 4y^3*z*(y/2z)^(-3) igot= this problem was so hard i couldn't get an answer

5) (3c^(-4) d^5)^(-2) * 12cd^(-4)

I KNOW IT'S KIND OF ALOT, BUT I'M DESPERATE, THANKS SO MUCH TO WHO EVER ANSWERS THIS QUESTION!!

Answer 1

Simplify the expression

1. Correct

2. Incorrect

6h-3h(h+1)

= 6h-3h²-3h ---Distribute -3h to (h+1). You forgot the negative sign.

= -3h²+3h

3. Correct

Solve if possible

1. Correct

Use substitution to solve the system of linear equations

1. Incorrect

x-0.5= 6

0.5x+0.2y= 8

x-0.5= 6

x= 6.5 ---Add 0.5 to both sides.

0.5(6.5)+0.2y= 8 ---Substitute 6.5 for x.

3.25+0.2y= 8 ---Simplify.

0.2y= 4.75 ---Subtract 3.25 from both sides.

y= 23.75 ---Divide both sides by 0.2.

(6.5, 23.75)

Simplify the expression. The simplified expression should have no negative exponents.

1. Incorrect

(2n^4)(3n)²

= (2n^4)(9n²)

= 18n^6

2. Incorrect

(r/3s)^(-3)

= [r^(-3)]/[(3s)^(-3)]

= (1/r³)/[1/(3s)³]

= (1/r³)/(1/27s³)

= (1/r³)*27s³

= 27s³/r³

3. Incorrect

(w^5)(7/w^4)²

= (w^5)[(7²)/(w^4)²]

= (w^5)[49/(w^8)]

= 49/w³

4. 4y³z[(y/2z)^(-3)]

= 4y³z[(y^(-3))/((2z)^(-3))]

= 4y³z[(1/y³)/(1/(2z)³)]

= 4y³z[(1/y³)/(1/8z³)]

= 4y³z(8z³/y³)

= 32z^4

5. ((3c^(-4))+d^5)^(-2)*12cd^(-4)

= (1/(81c^4)+d^5)^(-2)*12cd^(-4)

= (1/(81c^4)+(d^5)(81c^4)/(81c^4))^(-2)*

12cd^(-4)

= ((1+(d^5)(81c^4)/(81c^4))^(-2)*12cd^(-4)

... Super Speed Activated

= (6561c^8)/(1+(2d^5)(81c^4)+(d^10)

(6561c^8))*12cd^(-4)

= (6561c^8)/(1+(2d^5)(81c^4)+(d^10)

(6561c^8))*12c/(d^4)

= (78732c^9)/((d^4)+(2d^9)(81c^4d^4)

+(d^14)(6561c^8d^4))

...You owe me...