How do I go about solving these geometric equations

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I was doing the test I had missed the day before, so I had missed out on this lesson. I tried youtubing it, I already attempted the first page, which is probably wrong, I have no idea what to do

Help please?

prob 3a) area of a rectangle is L x W
L = 4
W = 2x - 3
4(2x - 3) = 44
8x - 12 = 44
8x = 56
x = 7m

prob 3b) perimeter of a triangle is the sum of all the sides
(2x + 1) + x + (4x - 4) = 32m
(7x - 3) = 32
7x = 35
x = 5 m

prob 4a) break up the shape into two rectangles
Mine were rect 1) 7 x 2 cm, and rect 2) 4 x X cm
Area of rect 1 = 14 cm sqr area of rect 2 = 4X cm sqr
14 + 4X = 30
4X = 16
X = 4 cm

prob 4b) perimeter of the shape means to add up all the sides
8 + 8 + 6x (the bottom and the sides)
2x + 2x + 2x + 2x + 2x (the top)
all the pieces are congruent. 3 of them equal 6x, so each piece is 2x
16 + 16x = 64
16x = 18
x = 3 m

44 = 4(2x - 3)

44 = 8x - 12

56 = 8x

x = 7

32 = 4x - 4 + x + 2x + 1

32 = 7x - 3

35 = 7x

x = 5