The answer to this question is <span>C. The student did not evaluate sqrt 16 and sqrt 25 before estimating sqrt 18.</span> The square roots of 16 and 25 are 4 and 5 respectively. He should have esimated that sqrt(18) is close to 4.2 instead of 17.
The root will touch the axis and bounce off when the exponent is even. In that case, that means (x + 2)² is the binomial that will bounce. Therefore, the root which bounces and touches the x-axis is x = -2.
