He bought 3 small notebooks (3*7=21) and 3 large notebooks (3*10=30)
21+30=51
Answer:
x= 20
Step-by-step explanation:
The three angles add to 90 degrees
x+2x+x+10 = 90
Combine like terms
4x+10 = 90
Subtract 10 from each side
4x +10-10 = 90-10
4x = 80
Divide by 4
4x/4 = 80/4
x = 20
Answer:He drove it for 126 miles
Step-by-step explanation:
$2.6, multiply 13 by .2 and you get 2.6
There can be no negative in a sqrt
so x+1 must be equal or greater then 0
x+1

0
x

-1
so all answers must be greater then or equal to -1
-1,0,1,2,3,4,5,6,7,8
(-1,infinity) is the domain