If you want at least 3 pounds of hamburgers, then $6 is enough to buy those 3 pounds of hamburgers. If you ONLY buy 3 Pounds, then you also have enough for 4 pounds of chicken. $3 a pound x 4 = $12. You have 2 dollars left to spare, which means you can buy another pound of hamburgers. So 4 pounds each are able to be purchased.
It's C) -3/4If you need the steps let me know. (:
<u>Question 8</u>
a^2 + 7a + 12
= (a+3)(a+4)
When factorising a quadratic, the product of the two factors should equal the constant term (12), and the sum of the two factors should equal the linear term (7). To find the two factors, list out the factors of 12 (1x12, 2x6, 3x4) and identify the pair that adds up to 7 (3+4).
An alternative method if you get stuck during your exam would be to solve it algebraically using the quadratic formula and then write it in the factorised form.
a = (-7 +or- sqrt(7^2 - 4(1)(12)) / 2(1)
= (-7 +or- sqrt(1))/2
= -3 or -4
These factors are the negative of the values that would go in the brackets when written in factorised form, as when a = -3 the factor (a+3) would equal 0. (If it were positive 3 instead, then in the factorised form it would be a-3).
<u>Question 10</u>
-3(x - y)/9 + (4x - 7y)/2 - (x + y)/18
Rewrite each fraction with a common denominator so you can combine the fractions into one.
= -6(x - y)/18 + 9(4x - 7y)/18 - (x + y)/18
= (-6(x - y) + 9(4x - 7y) - (x + y)) /18
Expand the brackets and collect like terms.
= (-6x + 6y + 36x - 63y - x - y)/18
= (29x - 58y)/18
= 29/18 x - 29/9 y
The answer is C. and E.
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Work shown below:
A. 500 divided by 6 equals 83.33.
B. 600 divided by 3 equals 200.
C. 100 divided by 4 equals 25. (CORRECT)
D. 150 divided by 5 equals 30.
E. 200 divided by 8 equals 25. (CORRECT)
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Hope this could help you.
I think it's 6.216 x 10^8 if this is about standard notation