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Consider the system of equations

 

\(\begin{align*} 5x - 2y &= 16, \\ 15x - 7y &= 51. \end{align*}\)


Multiply the first equation by some constant, so that in the resulting equation, the coefficient of  matches the coefficient of  in the second equation.

Enter the entire equation that results from multiplying the first equation by the constant.
 

 Sep 21, 2020
 #1
avatar+111127 
+1

Here is a hint:

Use the elimination method

Multiply the first one by 3

then subtract the second one from the first one.    That will get rid of the x'es

Then you solve for y

etc

 

You can ask for more help but show evidence that you have done something.

 

 

No one else answer over me.  

 Sep 21, 2020
 #2
avatar+27709 
+1

so that in the resulting equation, the coefficient of  ??  matches the coefficient of  ?? 

 

Not  answering over Melody....just pointing out the missing info in your Q

   Melody helped you if the  ??   is  'x'

       if the ??   is 'y'    you would multiply the first equation by  3.5   ....

 

cheeky

 Sep 22, 2020
 #3
avatar+111127 
+1

No EP

No child would be taught to multiply by 3.5 !      The maths is too unfriendly

 

They'd multiply by 3, just like I said. 

Subtract,

solve for y

then sub the y value back into either original formula and solve for x.

Melody  Sep 22, 2020

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