Question

(7x + 5y = 12) 4x + = 18

Answer 1

Ответ:

(7х+5у=12

(4х+у=18

(7х+5(18-4х)=12

(у=18-4х

7х+90-20х=12

7х-20х=12-90

-13х=-78

х=6

Answer 2

It seems there is a typographical error in the equation you provided. The equation "4x + = 18" has an equal sign without a coefficient or constant on the left side. I assume you meant to write a complete equation.

If you intended to write a separate equation, please provide the complete equation so I can assist you further. If you meant to connect the two equations, you can solve the system of equations for the values of x and y. The two equations you provided are:

1. 7x + 5y = 12
2. 4x = 18

To solve this system of equations, you can isolate 'x' in the second equation and then substitute it into the first equation:

From the second equation, you can solve for 'x': 4x = 18 x = 18 / 4 x = 4.5

Now that you have the value of 'x,' you can substitute it into the first equation:

7(4.5) + 5y = 12 31.5 + 5y = 12

Next, subtract 31.5 from both sides to solve for 'y':

5y = 12 - 31.5 5y = -19.5

Now, divide by 5 to find the value of 'y':

y = -19.5 / 5 y = -3.9

So, the solution to the system of equations is x = 4.5 and y = -3.9.