5x + y = 27
substitute: 5x + 4x = 27
combine: 9x = 27
divide (by 9): x = 3
The answer would be: D-100. The reasoning of this is because if you take 3 X 10 to the third power and did the exponent (10 to the third power in this case) and multiplied it you would obviously get 1,000 for an answer. Then would would do 1,000 X 3 to get 3,000.
We can use ratios and the cross-multiply-divide to find this.
The ratio 21:5 is avaliable via the question. We then need to compare that to the ratio x:100, the 100 being the percent and the x being the number of airplane parts.
21/5 = x/100
We can then solve for x to find the number of airplane parts. First we multiply by 100 on both sides to get 2100/5 = x. Therefore x = 420 and there are 420 airplane parts.
Since the divisor is in the form (x + #) or (x - #), This can be done by synthetic division.
First put the polynomial ion descending order: x^2 - 7x + 15
Take the coefficients of the terms and follow these steps:
3 | 1 -7 15
3 -12
___________ Bring down the 1, multiply the 3 by the 1 and place under the
1 -4 3 -7, then add.
Multiply 3 by -4, place under the 15, then add.
The bottom row is our answer. Since the problem started with a second power, the answer will start with a first power.
The bottom row are the coefficients of the terms and the last number is the remainder.
x - 4 remainder 3 ALSO WRITTEN x - 4 + 3/(x -3)