Answer:
Solve for y in the first equation.
Step-by-step explanation:
Given
3x+y=9
15x-3y = 1
Required
Determine the first step to avoid fractions
From the list of given options, the option that best answered the question is to Solve for y in the first equation.
Solving for y will let you substitute the expression for y in the second equation
Going by that:- Solve for y in the first equation.
[tex]3x + y = 9[/tex]
Subtract 3x from both sides
[tex]3x - 3x + y = 9 - 3x[/tex]
[tex]y = 9 - 3x[/tex]
Substitute 9 - 3x for y in the second equation
[tex]15x - 3y = 1[/tex] becomes
[tex]15x - 3(9 - 3x) = 1[/tex]
[tex]15x - 27 + 9x = 1[/tex]
Collect like terms
[tex]15x + 9x = 1 + 27[/tex]
[tex]24x = 28[/tex]
Divide both sides by 24
[tex]\frac{24x}{24} = \frac{28}{24}[/tex]
[tex]x = \frac{28}{24}[/tex]
Divide numerator and denominator by 4
[tex]x = \frac{7}{6}[/tex]
Substitute 7/6 for x in the [tex]y = 9 - 3x[/tex]
[tex]y = 9 - 3 * \frac{7}{6}[/tex]
[tex]y = 9 - \frac{7}{2}[/tex]
Solve fraction
[tex]y = \frac{18-7}{2}[/tex]
[tex]y = \frac{11}{2}[/tex]
Answer:
It's B (the one above is right)
Step-by-step explanation:
