Solve by completing the square x^2-x-7=0

Find a least squares solution of Ax=b by constructing and solving the normal equations.
${\displaystyle A=\left[\begin{array}{cc}3& 1\\ 1& 1\\ 1& 4\end{array}\right],b\left[\begin{array}{c}1\\ 1\\ 1\end{array}\right]}$
${\displaystyle \bar{x}=}$?

Consider the following equation.
${\displaystyle 3x+\frac{2}{3}-2y=2-y}$
Step 1 of 2: Express the given equation in slope-intercept form.

For each of the models listed below, predict y when x=2.
a) ${\displaystyle y=1.2+0.8\log x}$,
b) ${\displaystyle \log y=1.2+0.8x}$,
c) ${\displaystyle \ln y=1.2+0.8\ln x}$,
d) ${\displaystyle y^2=1.2+0.8x}$,
e) $\frac{1}{\sqrt{y}}=1.2+0.8x$

Determine whether the ordered pair is a solution to the given system of linear equations.
1.(5,3) ${\displaystyle \{\begin{array}{c}x-y=2\\ x+y=8\end{array}\}}$

Write the equation of a circle given the center and radius. center: (-4, -2); radius = 9

Solving the following equation. Then, determine if the equation has one solution, no solution, or infinite solutions. Show all your steps. 4x + 1 = 2(2x + 3)

What is the correct first step to slove this system of equations 4x-3y=-10
2x+3y=4