Please help which one is it ?

7x+8y=-18, 4x-9y=-3 solve the system of equations

Prove the divisibility of the following numbers: 25^9 + 5^7 is divisible by 30.also, read as (25 to the power of 9) + (5 to the power of 7) is divisible by 30. blank x 30what is the blank? ( it should be expressed in exponent form)

Dagne measures and finds that she can do a vertical jump that is 27.5% of her height.if dagne is 48 inches tall, how high can she jump? enter your answer in the box. inches