6x-5y=9
-18x+by=-27
What value of b will make the system of equations above have infinitely many solutions?

The average human heart beats 1.15 \cdot 10^51.15⋅10 5 1, point, 15, dot, 10, start superscript, 5, end superscript times per day. there are 3.65 \cdot 10^23.65⋅10 2 3, point, 65, dot, 10, start superscript, 2, end superscript days in one year. how many times does the heart beat in one year? write your answer in scientific notation, and round to one decimal place.

Find the zeros of each function. f(x) = 6x^2 - 7x - 20

Benjamin is making bow ties. how many 1/2yards lomg bow ties can he make if he has 18 feet of fabric?