△ABC is reflected across the y-axis on a coordinate plane, resulting in △A′B′C′. If the measure of ∠A is 50 degrees, what is the measure of ∠A′?

in degrees

David bought a poster for an art project. the poster is 2.7 feet wide and 3.9 feet tall. what is the area of the poster?

Can any one me with the answers to these questions asap?

John used linear combination to solve the system of equations shown. he did so by multiplying the first equation by -3 and the second equation by another number to eliminate the x-terms. what number did jonas multiply the second equation by? 4x-6y=23x+5y=11