Using the matrices below, perform the following operation:
x= [1 2]. y= [12 5]
[7 8]. [3 1]
2X + Y = ?

Find the area of a trapezoid with a height of 23, base 1 of 10 and base 2 of 18

Find two numbers if their sum is 91 and the ratio is 6: 7?

Aspacecraft can attain a stable orbit 300 kilometers above earth if it reaches a velocity of 7.7 kilometers per second. the formula for a rocket's maximum velocity v in kilometers per second is vequalsminus0.0098tplusc ln upper r, where t is the firing time in seconds, c is the velocity of the exhaust in kilometers per second, and r is the ratio of the mass of the rocket filled with fuel to the mass of the rocket without fuel. find the velocity of a spacecraft whose booster rocket has a mass ratio of 20, an exhaust velocity of 2.1 km/s, and a firing time of 15 s. can the spacecraft achieve a stable orbit 300 km above earth?