Lara says that she can use this picture to show that two pairs of congruent angles and one pair of corresponding congruent sides is enough information to prove that two
triangles are congruent. Is Lara correct?

no.

the statement itself is correct, but the picture is not showing that. so, this picture cannot be used to prove the statement.

Step-by-step explanation:

while it is correct that 2 pairs of congruent angles and one pair of a side that is enclosed between these 2 angles would be enough to prove that the triangles are congruent (that would be the ASA method), but the picture only identifies one pair of congruent angles (and one pair of congruent sides). and THAT is not sufficient.

no not all of them.

step-by-step explanation:

some of them have a square base.

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 -