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Which expression do you get when you eliminate the negative exponents of 4a^2 b^216a^-3 b

Identify the expression equivalent to 4(x + x + 7) − 2x + 8 − 4 by substituting x = 1 and x = 2.

The statements below can be used to prove that the triangles are similar. ? △abc ~ △xyz by the sss similarity theorem. which mathematical statement is missing? ∠b ≅ ∠y ∠b ≅ ∠z