Please help really really need this it's on topic systems of equation

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 -

6(h+1)/2=a

a=area

step-by-step explanation:

its the same thing as a square or rectangle but after multiplying two sides you need to divide it by two.

step-by-step explanation:

for volume, add base x height x width

c.

step-by-step explanation:

simple you would first have to get   a negative number where as 1 to be multiplied by 24 and then you would have to multiply 6 time 4 and then repeat that process until you reach your term