Multiply the first equation by -1
-3x-y=-4
2x+y=5
Add them up
-x=1
So x=-1
And y=7
So the first option is correct
Answer:
-1, -3, 2, 5, 6
Step-by-step explanation:
The numbers in the | | mean that it would be positive. Instead of being |-5|, it would be positive 5.
Answer:
117 cups
Step-by-step explanation:
two dozen cookies calls for 234cups of sugar
2 dozen cookies = 234 cups of sugar
How much sugar is needed to make one dozen cookies?
Let x = cups of sugar needed
1 dozen cookies = x cups of sugar
2 dozen cookies : 234 cups of sugar = 1 dozen cookies : x cups of sugar
2 : 234 = 1 : x
2 / 234 = 1 / x
Cross product
2*x = 234 * 1
2x = 234
x = 234 / 2
= 117 cups
Your options are wrong because none corresponds with the answer
Answer:
864 cubic meters
Step-by-step explanation:
Rectangular prism = 5x9x12=540
Triangular prism = 1/2(9)(6)(12)=324
540+324=864 cubic meters
Answer: 6i) 6a² - 2ab
6ii) -2b³
6iii) b³ + 7b² - 49b
<u>Step-by-step explanation:</u>
6i) (a + b)(5a - 3b) + (a - 3b)(a - b)
= 5a² - 3ab + 5ab - 3b² + a² - ab - 3ab + 3b²
= 5a² + 2ab - 3b² + a² - 4ab + 3b²
= 6a² - 2ab
6ii) (a - b)(a² + b² + ab) - (a + b)(a² + b² - ab)
= a³ + ab² + a²b - ab² - a²b - b³ - (a³ + ab² - a²b -ab² + a²b + b³)
= a³ - b³ - (a³ + b³)
= a³ - b³ - a³ - b³
= -2b³
6iii) (b² - 49)(b + 7) + 343
= b³ + 7b² - 49b - 343 + 343
= b³ + 7b² - 49b
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Please post #7 on a different question.
