Mathematics
cjh
2021-05-04 21:37:18
Which value for x makes the open sentence true? 9 • 8 – 2x + x2 ≥ x3 + x2 A: 7 B: 6 C: 5 D: 4
ANSWERS
racheldmarrero
2021-05-05 00:09:14

basically either subsitute or solve I will simplify to make easier work so PEMDAS Parenthasees Exponents multiply or divide whichever comes first add or subtract whichever comes first 9 times 8=72 I will assume that x2=x^2 or x squared so left is simplified x^3+x^2 so 72-2x+x^2>x^3+x^2 subtract x^2 from both sides since they cancel each other out 72-2x > x^3 add 2x to both sides 72 > x^3+2x factor 72 > x(x^2+2) now subsitute 7,6,5,4 if x=4 then 4(4^2+2)=4(16+2)=4(18)=72 72 > 72 true since all the other numbers are smaller, the only sentence that will work is 7 or A the answer is A 7

ADD ANSWER