Simplify 5a + 5b - 6a + 8b​

The measures of the angles in △abc are given by the expressions in the table. angle measure angle a 65° angle b (3x−10)° angle c (2x)∘ find the value of x. then find the m∠b and m∠c.

Which has the greater energy, light of wavelength 519 nm or light with a frequency of 5.42 x 10^8 sec^-1?

Rena used the steps below to evaluate the expression , when . step 1: substitute into the expression. step 2: simplify the parentheses. step 3: evaluate the power to a power. step 4: use reciprocals and find the value. in which step did rena make the first error?