$(a+b)^2=a^2+2ab+b^2\qquad(*)\\\\\\x^2+6x-4=0\qquad\text{add 4 to both sides}\\\\x^2+2(x)(3)=4\qquad\text{add}\ 3^2=9\ \text{to both sides}\\\\\underbrace{x^2+2(x)(3)+3^2}_{(*)}=4+9\\\\(x+3)^2=13\Rightarrow x+3=\pm\sqrt{13}\qquad\text{subtract 3 from both sides}\\\\x=-3\pm\sqrt{13}$

8 0

3 years ago

Simplify radical expression <br><br> √10z^5 - z^2 √10z

SCORPION-xisa [38]

Answer:

√10z^3(z - 1)(z + 1).

Step-by-step explanation:

The GCF is √10z* z^2

= √10z^3

So factoring we get

√10z^3(z^2 - 1) The expression in brackets is difference of 2 squares so:

= √10z^3(z - 1)(z + 1)

5 0

1 year ago

State whether each percent of change is a percent increase or a percent decrease. Then find the percent of increase or decrease

Otrada [13]

Percent decrease. 41%
percent change= (new-old)/old *100
= -41 % the negative means decreasing

8 0

2 years ago