alexquiroga831 alexquiroga831
  • 01-12-2020
  • Mathematics
contestada

What is the value of x in the solution to this system of equations?

4x+7y=85

x=2y−5

A. x = -9
B. x = 9
C. x = 8
D. x = 3

Respuesta :

sophiew4
sophiew4 sophiew4
  • 01-12-2020

Answer:

B

Step-by-step explanation:

I used substitution to solve this system. I'll run through all of my steps below:

[tex]4x+7y=85\\x=2y-5[/tex]

I'm going to replace the 'x' values in the first equation with the entire second equation.

[tex]4(2y-5)+7y=85[/tex]

[tex]8y-20+7y=85\\15y-20=85\\15y=105\\y=7[/tex]

Now that we know what y equals, we can go back and solve for x.

[tex]x=2(7)-5\\x=14-5\\x=9[/tex]

Hope this helps!

Answer Link

Otras preguntas

It will be difficult to institute fiscal policy in a stabilizing manner because politicians will find
What was his mistake?
find the radius please help and explain!!
You have now identified whether crabs are able to see plankton they eat near the ocean floor. Based on your answer, explain how this information can be used to
The construction crew for a new house will dig a hole in the shape of a rectangular prism for the house's foundation. the hole will be 48ft long, 39ft wide, and
pls help me answer thiss. I really really need help! thank u
Who were the allies during 9/11
A total of 720 tickets were sold for the school play. They were either adult tickets or student tickets. There were more student tickets sold than adult tickets
The expression 3(x^2 - 1) - (x^2 - 7x + 10) is equivalnt to
What should the concluding paragraph of a narrative essay include? (A. B. a summary of the main idea of the essay and its significance facts and sensory details