Plz show your work! :)

x = 19

Step-by-step explanation:

The sum of the three angles is 180°

So,

(5x + 4) + (x - 2) + (3x + 7) = 180

9x + 9 = 180

9x = 180-9

9x = 171

x= 171 ÷ 9

x = 19

d) 30 units^2

area of rectangle = l × b

we know,

length = 10 unit

breadth = 3 unit

applying the formula,

= l × b

= 10 × 3

= 30 unit^2

happy to

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