Question

Solve for x in the equation x^2-12x+36 = 90
x=6+3(sqrt)10
x=6+2 (sqrt)7
x=12+3(sqrt)22
x=12+3(sqrt)10

Answer 1

Step-by-step explanation:

${x}^{2} - 12x + 36 = 90 \\ {x}^{2} - 12x - 54 = 0$

Let a=1, b=-12, c=-54

Use formula

$\frac{ - b + - \sqrt{ {b}^{2} - 4ac } }{2a}$

You will get

$x = 6 + 3 \sqrt{10} \\ x = 15.48683298 \\ or \\ x = 6 - 3 \sqrt{10} \\ x = - 3.48683298$

Answer 2

Answer:

x = 6 + 3$\sqrt{10}$

Step-by-step explanation:

if you 'un-foil' the equation $x^{2}$ - 12x + 36 = 90 you will get the following:

(x - 6)^2 = 90

take the square root of each side and you will get the following:

x - 6 = $\sqrt{90}$

Add 6 to each side

x = 6 + $\sqrt{90}$

simplify $\sqrt{90}$ to be $\sqrt{9}$ x $\sqrt{10}$  which equals 3 $\sqrt{10}$

Final answer:  6 + 3$\sqrt{10}$