What word phrase can you use to represent the algebraic expression 7x?

How long does it take natsumi to clean up after she is done? table: .area time30. 245. 2.7560. 3.5

Which expression is the factorization of x^2+10+21

1. ∠1 is complementary to ∠2 and ∠3 is complementary to ∠2. subtraction property of equality 2. m∠1 + m∠2 = 90 and m∠3 + m∠2 = 90 substitution 3. m∠1 + m∠2 = m∠3 + m∠2 definition of complementary 4. m∠1 = m∠3 given