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

What is (6x4 - 7x3 - 153x2 + 175x + 75) divided by (x + 5)?
Write an expression equivalent to the one below. -2m - 8 +4(3m - 9) please help me!!
Which items are properties of bases? soapy sour bitter slick poisonous
Graph the functions and approximate an x-value in which the exponential function exceeds the polynomial function. y = 4^x y = 7x^2 + 4x - 2 a. x=-1 b. x=0 c.
What is a characteristic of a successful budget
The original price of a computer is $579. Which coupon is a better deal? A) SAVE 25% ON ANY COMPUTER B) SAVE $150 ON ANY COMPUTER C) SAVE $75 PLUS 5% OFF ON A
A dog will eat 4 cups of dog kibble a day. There is 100 cups of dog food in a 50lb bag. How much dog food will a dog eat in a year? Please show your work.
relate peak flow to lung function
What makes fundamentalism different from other religious expressions??
What year did slavery started and what year did it endend?