The student added 9 1/2 instead of adding -9 1/2
Answer:
If It was a Fraction it'd be 8/5
Step-by-step explanation:
If the polynomial is of the form x^2+bx+c (ie., no factor in front of the x^2!!) then you can look for numbers that add up to b and multiply to c.
So in this case: what two numbers, when added, give -2 and when multiplied, give 1? A little trial and error gives you -1 and -1.
So the factorization is (x-1)(x-1). This is zero for x=1. There is only one zero.
3.35 - 3.10 = .25
.25/3.35 = .0746
.0746*100 = 7.46 or 7.5 rounded