11. 5x^2-30=0
+30 to both sides
5x^2=30
÷5 both sides
x^2=6
square root both sides
x= +square root 6 ,- square root 6
12. 4x^2+10=26
-10 both sides
4x^2=16
÷4 both sides
x^2=4
square root both sides
x=+2,-2
13. a=72yrd^2
l=2w
w=?
a=l×w
72=2w×w
72=2w^2
÷2 both sides
36=w^2
square root both sides
w=+6,-6
a measurement can't be - so w=6
Plug into l=2w
l=2×6
l=12
w=6
Answer:
-2 from both sides
Step-by-step explanation:
32=5x+2
-2 -2
________
30=5x
__=__
5 5
6=x
Answer:
You can't find y in this way
Step-by-step explanation:
You should know the value of x
But you can say
Y=7x
Answer:
600
Step-by-step explanation:
