Use a half-angle identity to find the exact solution of cos3pi/8

If f(x)=x^3 and g(x)=2x+7 when g(x)=-5

Follow these steps using the algebra tiles to solve the equation −5x + (−2) = −2x + 4. 1. add 5 positive x-tiles to both sides and create zero pairs. 2. add 4 negative unit tiles to both sides and create zero pairs. 3. divide the unit tiles evenly among the x-tiles. x =

Zahra runs a 500-meter race at a constant speed. which graph shows her distance from the finish line during the race?