Perform the indicated operations.
(8x9 - 9x8 + 2x7 + 2) + (2x9 + 6x8 + 7x7 + 6)
16x48 + 8
8x9 + 8x8 + 14x7 - 7
10x9 - 3x8 + 9x7 + 8
10x18 - 3x16 + 9x14 + 8
2007-06-23 16:01:40 · 5 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
(8x^9 - 9x^8 + 2x^7 + 2) + (2x^9 + 6x^8 + 7x^7 + 6)
10x^9 - 3x^8 + 9x ^7 + 8
2007-06-23 16:13:57 · answer #1 · answered by Keith 3 · 0⤊ 1⤋
This exercise teaches about grouping as well as the order of operations.
Since the parentheses don't change the order of operations, we can ignore them. Now rearrange the terms:
8x9 + 2x9 - 9x8 + 6x8 + 2x7 + 7x7 + 2 + 6
Using the distributive property: 8x9 + 2x9 = (8+2)x9 = 10x9
Next, -9x8 + 6x8 = (-9+6)x8 = -3x8
Then, 2x7 + 7x7 = (2+7)x7 = 9x7
Finally, 2 + 6 = 8
Add all these terms together for your answer.
2007-06-23 23:23:54 · answer #2 · answered by Katy D 4 · 0⤊ 1⤋
The point of the exercise is to remind you that you have to multiply before adding or subtracting.
(72 - 72 + 14 + 2) + (18 + 48 + 49 + 6)
First parenthesis = 16
Second parenthesis = 121
16 + 121 = 137
Do the others in a similar way.
2007-06-23 23:06:53 · answer #3 · answered by ecolink 7 · 0⤊ 1⤋
Well, how many x9 do you have?
You have 8 (in the first bracket) and 2 (in the second bracket).
So you have 10 x9.
So the only possible answer is the third one. You can do the other terms similarly to check, if you want.
2007-06-23 23:16:35 · answer #4 · answered by tsr21 6 · 0⤊ 1⤋
10x9 - 3x8 + 9x7 + 8
2007-06-24 12:07:18 · answer #5 · answered by UNIQUE 3 · 0⤊ 0⤋