Which shows a difference of squares?
10y^2 – 4x^2
16y^2 – x^2
8x^2 – 40x + 25
64x^2 – 48x + 9

Hello,

1) (√10 y)²-(2x)²
2) (4y)²-x²
3)8x²-40x+25=8(x²-5x)+25
=8(x²-2*5/2*x+25/4)+25-8*25/4
=8(x-5/2)²-25
=8(2x-5)² /4 -25
=[√2*(2x-5)]²-5²

4)
64x²-48x+9=(8x-3)²-0²

When rates are expressed as a quantity of 1, such as 2 feet per second or 5 miles per hour, they are called unit rates. if you have a multiple-unit rate such as 120 students for every 3 buses, and want to find the single-unit rate, write a ratio equal to the multiple-unit rate with 1 as the second term.