:( solve equation for y. then find the value of y for the given value of x?

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15x + 4y = 9
4y = 9 - 15x
y = (9 - 15x)/4

Answer: (9 - 15x)/4 OR 9/4 - 15/4x
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= 9/4 - 15/4(- 3)
= 9/4 + 45/4
= 54/2 or 27/2

Answer: y = 27/2 or 13 1/2

Checking original equation:
15(- 3) + 4(27/2) = 9
- 45 + 108/2 = 9
- 45 + 54 = 9
9 = 9...Show more

Solve the equation for y would possibly mean making y the subject of the equation, or in other words, changing our equation to "y = ..."
So we do this:
4y = 9 - 15x
y = (9 - 15x) / 4

Now substituting into this equation, the given value of x:
y = [ 9 - 15 (-3) ] / 4
y = [ 9 + 45 ] / 4
y = 54 / 4
y = 13.5...Show more

First you need to plug X into your equation. So,,,

15X + 4Y = 9 becomes

(15*-3) + 4Y = 9 Simplify your equation

-45 + 4Y = 9 Now simply balance the equation so y is alone by adding 45 to both sides

-45+45 + 4Y = 9+45

4Y = 54 Then divide by 4 to make y all alone and you have your answer.

4y/4 = 54/4

y = 13.5...Show more

Solving the equation means simplifying it.
Like this:
15x+4y=9
or, 4y=9-15x
0r, y=(9-15x)/4
Now y will have different values, for different values of x.But it's given that x=-3, So, y=(9-15x(-3))/4
=(9+45)/4
=27/2=13.5...Show more

15x + 4y = 9
subtract 15x on both sides: 4y = 9 - 15x
divide both sides by 4: y = 9/4 -15x/4 = 2 1/4 - 3 3/4 x
Now, for x = -3, this gives:
y = 2 1/4 - 3 3/4 * -3 = 2 1/4 + 11 1/4 = 13 1/2...Show more