Answer:

Step-by-step explanation:

Let's apply the formula (x+y)² = x² + 2xy + y²
Here, x = -a and y = b
So,
= (-a)² + 2(-a)(b) + (b)²
= a² - 2ab + b²
Hence, it has been proved that (-a + b)² = a² - 2ab + b².
![\rule[225]{225}{2}](https://tex.z-dn.net/?f=%5Crule%5B225%5D%7B225%7D%7B2%7D)
Hope this helped!
<h3>~AH1807</h3>
Answer:
The percent error is 40%.
Step-by-step explanation:
5 (actual time) - 3 (estimated time) = 2
2 divided by 5 (actual time) = 0.4
0.4 x 100 = 40%
Answer:
3 • (2xy - 7) • (xy + 2)
Step-by-step explanation:
(((2•3x2) • y2) - 9xy) - 42
6x2y2 - 9xy - 42 = 3 • (2x2y2 - 3xy - 14)
Answer:
40
Step-by-step explanation:
3u-> 60
1u-> 20
2u->40