SOLUTION: 3x/6 -4/12 =7 ; -36x +24=-504
In the following pair of equations, both sides of the equation on the left were multifplied by a number to get the equation on the right. What is
Algebra.Com
Question 309282: 3x/6 -4/12 =7 ; -36x +24=-504
In the following pair of equations, both sides of the equation on the left were multifplied by a number to get the equation on the right. What is the number?
I know the answer is -72.
If you could please help me find out how to get that answer that would be so wonderful.
Thank you!!
Answer by jim_thompson5910(35256) (Show Source): You can put this solution on YOUR website!
Well a quick and easy way to get a common multiple of 2 (or more) numbers is to simply multiply them. For instance, a common multiple of 17 and 5 is 17*5=85
In this case, a common multiple between 6 and 12 is 6*12=72. It turns out that the numbers that share the common multiple will go into that common multiple. Ie and . What this means is that you can effectively clear out the denominators of the fractions leaving you with integer terms.
For instance, multiply 72 by to get . In the given problem, the only difference is that 36x is really -36x. So instead we must multiply both sides by -72.
Another quick way to realize that -72 is the magic number is to look at the right side. This side already has an integer which will make life easier for us. Take the number 7 and multiply it by some unknown number 'k' to get 7k. This is now equal to the new right side of -504. Set them equal to get 7k=-504. The task now is to solve the equation 7k=-504. Sure enough, solving the equation will get us k=-72 which is the number we're looking for.
RELATED QUESTIONS
I need to solve for x on the following equations. I honestly don't know what to do.... (answered by fcabanski)
How to solve: four times the sum of three times a number and -6 is 12
4(3x-6)=12... (answered by BigToosie)
I have to solve the equation below. It is a multiple choice question so I also listed... (answered by Edwin McCravy)
200 =600(a+1)/24
200 x 24 = 600(a+1) (by multiplying both sides of the... (answered by ainsworth50)
Solve the system by graphing both equations on the same axes. Give the ordered pair for... (answered by wilft1)
Please help! Determine whether the ordered pair is a solution of the inequality. (2,19);... (answered by stanbon,Alan3354)
Find the coordinates of the vertices of the triangle whose sides are contained in the... (answered by funmath)
Hong drove 792 miles in 11 hours.
At the same rate, how long would it take him to drive (answered by rfer,meay7c)
I've been working on an assignment and I'm stumped. I have to solve quadratic equations... (answered by MathLover1)