Which numbers make a perfect square

2*2=4

3*3=9

4*4=16

5*5=25

6*6=36

7*7=49

8*8=64

9*9=81

10*10=100

Step-by-step explanation:

c

c

c

c

c

c

c

cc

c

step-by-step explanation:

see explanation

step-by-step explanation:

a

(6r + 7) + (13 + 7r) ( remove brackets and collect like terms )

= 6r + 7 + 13 + 7r

= 13r + 20

b

remove brackets and collect like terms

13 - r - 1 + r

= 12 - r

c

remove brackets and collect like terms

= - 8 - r + 2r - 4

= - 12 + r

d

remove brackets and collect like terms

= 7r - - - 6r

[-   - = - - = - ]

= r -