Question

I need help with question 20​

Answer 1

Step-by-step explanation:

∠1 + ∠2 = 180° (angles on a straight line are supplementary)

x^2 + 3y + 20y + 3 = 180

x^2 + 23y = 177 --(1)

∠1 = ∠3 (vertically opposite angles)

x^2 + 3y = 3y + 4x

x^2 - 4x = 0

x(x - 4) = 0

x = 0 or x = 4

Sub x = 0 and x = 4 into (1):

0^2 + 23y = 177

y = 7.696 (3d.p.)

4^2 + 23y = 177

23y = 161

y = 7

therefore, x = 0 and y = 7.696 or x = 4 and y = 7

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