91Ó°ÊÓ

Factor. $$ -x^{4}+7 x^{2}+18 $$

Use a graphing calculator to find any solutions that exist accurate to two decimal places. $$ -x^{2}+13.80 x=47.61 $$

Solve. Round any irrational solutions to the nearest thousandth. \( 8 x^{3}+1=4 x^{2}+2 x \)

A baseball is popped up with an upward velocity of \(72 \mathrm{ft} / \mathrm{sec} .\) Its height in feet, \(h(t),\) after \(t\) seconds is given by $$ h(t)=-16 t^{2}+72 t $$ a) Find an equivalent expression for \(h(t)\) by factoring out a common factor with a negative coefficient. b) Perform a partial check of part (a) by evaluating both expressions for \(h(t)\) at \(t=1\)

Factor. $$ y^{2}(y+1)-4 y(y+1)-21(y+1) $$

Factor. $$ y^{2}(y-1)-2 y(y-1)+(y-1) $$

Solve. Round any irrational solutions to the nearest thousandth. $$ 27 x^{3}+18 x^{2}=12 x+8 $$

A water rocket is launched upward with an initial velocity of \(96 \mathrm{ft} / \mathrm{sec} .\) Its height in feet, \(h(t),\) after \(t\) seconds is given by $$ h(t)=-16 t^{2}+96 t $$ a) Find an equivalent expression for \(h(t)\) by factoring out a common factor with a negative coefficient. b) Check your factoring by evaluating both expressions for \(h(t)\) at \(t=1\)

Tori has factored a polynomial as \((a-b)(x-y)\) while Tracy has factored the same polynomial as \((b-a)(y-x) .\) Can both be correct? Why or why not?

Use a graphing calculator to find any solutions that exist accurate to two decimal places. $$ -x^{2}+3.63 x+34.34=x^{2} $$