A number is equal to the sum of half a second number and 3. The first number is also equal to the sum of one-quarter of the second number and 5. The situation can be represented by using the graph below, where x represents the second number. On a coordinate plane, a line goes through (0, 3) and (8, 7) and another line goes through (0, 5) and (8, 7). Which equations represent the situation? y= one-half x + 3 and y = one-fourth x + 5 y = 3 x + one-half and y = 5 x + one-fourth y = 2 x + 3 and y = 4 x + 5 y = 3 x + 2 and y = 5 x + 4

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?