You can add or subtract a number from both sides
Step-by-step explanation:
x=8-y
2x-y=7
2(8-y)-y=7
16-2y-y=7
-3y=-9
y=3
x=8-y
x=8-3=5
Answer:
The first one is by using your mind. If you know that factorial of any non negative integer denoted by n!
defined as
n!=n(n−1)(n−2)⋯3⋅2⋅1
then 5!=5∗4∗3∗2∗1. You can calculate it in your mind which will give you 5!=120.
That's it.
The next method is using your calculator. In my calculator Casio fx-991es, I pressed 5 and then shift+x−1
button and I got 120. Similarly, you can use Google to calculate it like I did and got this.
Step-by-step explanation:
Answer:
6. 2
7. 13
8. 10
9. -29.78
Step-by-step explanation:
6. 3(1) - 1
3-1
2
7. -2(-2)+9
4 + 9
13
8. 2(3) + 4
6 + 4
10
9. 3.8(-7.6) - .9
-28.88 - .9
-29.78
Answer:
14..........................