I really need help...Will mark brainiest

x² + 18x +81

x² - 14x +49

4x²- 4x - 1

Step-by-step explanation:

multiply the x in the first parentheses by x and 9 in the other parentheses and

multiply the 9 in the first parentheses by x and 9 in the other parentheses and add all together

(x+9)(x+9)

x² + 9x + 9x + 81

x² + 18x +81

multiply the x in the first parentheses by x and -7 in the other parentheses and multiply the -7 in the first parentheses by x and -7 in the other parentheses and add all together

(x-7)(x-7)

x² -7x - 7x +49

x² - 14x +49

(2x-1)² is the same as (2x-1)(2x-1)

multiply the 2x in the first parentheses by 2x and -1 in the other parentheses and multiply the -1 in the first parentheses by 2x and -1 in the other parentheses and add all together

(2x-1)(2x-1)

4x²-2x-2x+1

4x²- 4x - 1

answer: 7 x 2/5 = 2.8 hours, is your answer. your welcome! : 3

step-by-step explanation: first work out how long it took to hose 1/7 of the lawn which is 2/5 hours. times that by 7 to get the whole lawn.

sorry i don't know the other answer. i didn't learn what a proportional relationship is.