Math(please check)
posted by Hannah .
Simplify each expression:
1) (x+8)^2 = x^2 + 64
2) (x2)^3 = x^3  8
3) (x2y)(x+y) = x^2  xy 2y^2
4) (x+2)(x^2+3x2) = x^3 + 5x^2 + 4x4
Are my answers correct?

Numbers 3) and 4) are correct.
For numbers 1) and 2), you have missed out terms, probably you have not used the right standard formulae.
(a+b)² = a² + 2ab + b²
(ab)² = a²  2ab + b²
(a+b)³ = a³ + 3a²b + 3ab² + b³
(ab)³ = a³  3a²b + 3ab²  b³
If you are in an examination where you do not have an easy way to double check the standard formulae, you can treat
(a+b)² = (a+b)(a+b)
which you seem to have no problem solving. 
so for (x+8)^2 i would use
a^2 + 2ab + b^2 and a would be 8 but what is b? Would it be 64?
Respond to this Question
Similar Questions

Algebra 1: 8th Grade
Simplify each expression. Write your answers using positive exponents. Check Answers Please: 1) 2^3*2^4 = 2^7 2)10^6/10^9 = 1/10^3 3)3^5*3^1 = 3^6 4)5^7*5^4 = 5^3 5)9^3/9^10 = 9^13 6) 4^11/4^8*4^2 = 4^5 7) a^2*a^3 = a^5 8)b^9/b^4 … 
Math
Please check my work. 1) 64 divide 4 = 16 2) 144 divide (9) = 16 3) Simplify 9 and a small 2 = 81 4) Simplify (3) and a small 3 = 27 5) Add 4/11 + 5/11 = 1/11 6) subtract 5/11 [3/11] = 8/11 7) multiply [7/8] • [2/4] … 
Algebra (check my answers)
Please check these answers. Multiply 7(2a2 4) = 14a2 + 28 Multiply 0.5(a + b 5) = 0.5a + 0.5b  2.5 Factor bx  by + bz = b(x  y + z) Combine like terms (simplify) 12x + 4  11y  6x  9  y = 6x  12y  5 Evaluate the expression … 
Algebra
Can you please check my work? You have helped other students I know. Thank you:) Multiply 7(2a2 4) = 14a2 + 28 Multiply 0.5(a + b 5) = 0.5a + 0.5b  2.5 Factor bx  by + bz = b(x  y + z) Combine like terms (simplify) 12x + 4  
algebra 2
1.Simplify the difference. n^2  lOn+24 9 / n^2  13n + 42 — 7 A. n13/n7 <<< B. n4/n7 C. n13 2.Simplify the complex fraction. y1/y^2+y6/y6/y+3 A.(y1)(y6)/(y+3)^2(y2) B. y1/(y6)(y2) C.(y1)(y6)/(y+3)(y2)<<< … 
Math check my answers
Please check my answers on the following questions Simplify: (X^6)^1/2 = x^3 1000000^1/6 I don't know this one (64n^12)^1/6 = 1/0.5n^2 (9n^4)^1/2. = 3n^2 36^3/2 = my answer is 2 in the index of the aware root of 36^3 343^4/3 I don't … 
Algebra 1Please, check my answers!
Multiply. Simplify your answer. 1. (n + 3/n 5) x (n^2  5n) A: n^2 + 3n 2. (6xy^2/2x^2y^6) x (6x^4y^4/9x^3) A: 2 3. (3h^3  6h/10g^2) x (4g/g^2  2g) (This is the correct expression. There is no typo.) A: ? 
Math Please Check
Please check my answers! Thank you! Simplify the following expressions. Collapse “x” terms, and/or simplify fractions and exponents. 1.) (12/5) / (36/20) = 4/3 2.) x^13*x^3 = x^16 3.) x^4 / (x^2)^3 = 1/x^2 4.) x^3 / x^2 = x^5 … 
Algebra
1. Simplify the expression: 4√18+5√32 A.45√2 B.32√2 C.116√2 D.9√50 2. Simplify the expression: 7√53√80 A.5√5 B.4√75 C.5 D.4√75 3. Simplify the expression: √21(√3+√14) … 
Algebra
1.Simplify the radical expression. √5+6√√5 A.5√5 B.7√10 C.7√5 D.5√10 2.Simplify the radical expression. 2√6+3√96 A.14√6 B.14√96 C.5√96 D.50√6 3.Simplify …