-5 times -4 is 20 since a negative and a negative give u a positive
Rewrite 2x^2+x=15 as <span>2x^2+ x - 15 = 0. Use your favorite method to solve this for x. I prefer synthetic div., so will check out whether or not 2 is a root:
____________
2 / 2 1 -15
4 10
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2 5 -5 Since there is a non-zero remainder, 2 is NOT a root. Eliminate the 3rd answer choice.
Try -3. If used as a divisor in synth. div., will the remainder be zero or not zero? If zero, then -3 is a solution / root.
And so on.</span>
Answer:
45 girls
Step-by-step explanation:
- Remark
- There are only 2 choices for gender. So if the class is 60% girls, the there must be 100 - 60 = 40% for the boys.
- But we are told that the boys are 30 in number.
- Let x = the total number of students.
Solution
- 40/100 * x = 30 Change the % to a decimal
- 0.4 x = 30 Divide both sides by 0.4
- 0.4 x / 0.4 = 30 / 0.4 Do the division
- x = 30/0.4
- x = 75 students in total
Formula
Total of Boys and Girls = Number of boys + number of girls.
Givens
- Total = 75
- Number of boys = 30
Solution II
- 75 = x + 30 Subtract 30 from each side
- 75 - 30 = x +30 - 30
- 45 = x
- There are 45 girls in the class.
9 yards total because the quarterback didnt gain any yards during the second play