Determine if the pair of terms are like terms. if so, combine them. a) 3b and 4b^2b) 2x and -5xc) 2ab and -3ab

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Which sum or difference identity would you use to verify that cos (180° - q) = -cos q? a.) sin (a -b) = sin a cos b – cos a sin b b.) cos (a -b) = cos a cos b – sin a sin b c.) cos (a -b) = cos a cosb + sin a sin b d.) sin (a + b) = sin a cos b + cos a sin b

Proving the parallelogram diagonal theoremgiven abcd is a parralelogam, diagnals ac and bd intersect at eprove ae is conruent to ce and be is congruent to de