Hi, can someone explain the parallelogram angle theorem? i'm having trouble understanding this

Which shows the correct substitution of the values a,b and c from the equation 1=-2x+3x^2+1

Factor the expression using gcf 9b+45

In the diagram, the ratios of two pairs of corresponding sides are equal to prove that almn - axyz by the sas similarity theorem, it also needs to be shown that x 6 z un z zz un = 2x zləzz lezy