Answer:

Step-by-step explanation:
You can use trigonometry specially the cos rule in this case. I can’t send the other pictures. But using the cos rule you can check whether the angle is 90
Answer:
2(x + y)
Step-by-step explanation:
You can pull out a 2 from the expression.
So divide 2x by 2 and 2y by 2.
2x/2 = x
2y/2 = y
2(x + y)
For 6 plug in each of the answers for x and see if the product =3.2
Answer for 6: A
For 7 you turn the percentage into a decimal and multiply that by the number in which you know and you find the answer.
Answer for 7: D
Answer:
none of these
Step-by-step explanation:
A number is divisible by 10 if the last digit of the number is 0. The numbers 20, 40, 50, 170, and 990 are all divisible by 10 because their last digit is zero, 0.