Question

What is the answer for;
a. 7×6
b. √729
c. |x+3|=2x+5

Answer 1

`a.\ 7*6=42\\\\b.\ √(729)=27\ \text{because}\ 27^2=729`

`c.\ |x+3|=2x+5\\\\|x+3|=\left\{\begin{array}{ccc}x+3&for&x\geq-3\\-x-3&for&x < -3\end{array}\right\\\\(1)\ x < -3\to x\in(-\infty;\ -3)\\\\-x-3=2x+5\ \ \ |+3\\\\-x=2x+8\ \ \ |-2x\\\\-3x=8\ \ \ \ |:(-3)\\\\x=-(8)/(3)\\\\x=-2(2)/(3)\\otin(-\infty;\ -3)\\\\(2)\ x\geq-3\to x\in\left<-3;\ \infty\right)\\\\x+3=2x+5\ \ \ \ |-3\\\\x=2x+2\ \ \ \ |-2x\\\\-x=2\ \ \ |\cdot(-1)\\\\x=-2\in\left<-3;\ \infty\right)\\\\Answer:\ x=-2`