Which equations are in standard form? Check all that apply y = 2x + 5 2x + 3y = –6 –4x + 3y = 12 y = y equals StartFraction 3 Over 2 EndFraction x minus 9.x – 9 StartFraction one-half EndFraction x plus 3 equals 6.x + 3 = 6 x – y = 5 5x + 3y = 5 x plus 3 y equals StartFraction one-half EndFraction.
The Correct Answer and Explanation is :
To determine which equations are in standard form, we need to recognize the general form of the equation of a line in two variables, which is:
[
Ax + By = C
]
Where:
- ( A ) and ( B ) are integers (with ( A ) being nonzero),
- ( x ) and ( y ) are variables,
- ( C ) is a constant.
The equation should have all variables on one side, and the coefficients of ( x ) and ( y ) should be integers.
Let’s go through the equations one by one and check if they are in standard form:
- ( y = 2x + 5 )
This equation is not in standard form because it is written in slope-intercept form ( y = mx + b ). To put it in standard form, subtract ( 2x ) from both sides:
[
-2x + y = 5
]
This would be in standard form. - ( 2x + 3y = -6 )
This equation is in standard form. It has the format ( Ax + By = C ), with ( A = 2 ), ( B = 3 ), and ( C = -6 ). - ( -4x + 3y = 12 )
This equation is in standard form. It has ( A = -4 ), ( B = 3 ), and ( C = 12 ). - ( y = \frac{3}{2}x – 9 )
This equation is in slope-intercept form. To put it into standard form, multiply through by 2 to eliminate the fraction:
[
2y = 3x – 18
]
Then, subtract ( 3x ) from both sides to get:
[
-3x + 2y = -18
]
Now, it is in standard form. - ( \frac{1}{2}x + 3 = 6 )
This equation is not in standard form. First, subtract 3 from both sides:
[
\frac{1}{2}x = 3
]
Then multiply through by 2 to eliminate the fraction:
[
x = 6
]
This is not in standard form. - ( x – y = 5 )
This equation is in standard form. It has ( A = 1 ), ( B = -1 ), and ( C = 5 ). - ( 5x + 3y = 5 )
This equation is in standard form. It is already in the correct form ( Ax + By = C ), with ( A = 5 ), ( B = 3 ), and ( C = 5 ). - ( x + 3y = \frac{1}{2} )
This equation is not in standard form because of the fraction on the right side. To convert to standard form, multiply through by 2:
[
2x + 6y = 1
]
Now, it is in standard form.
Summary of equations in standard form:
- ( 2x + 3y = -6 )
- ( -4x + 3y = 12 )
- ( -3x + 2y = -18 ) (from the equation ( y = \frac{3}{2}x – 9 ))
- ( x – y = 5 )
- ( 5x + 3y = 5 )
- ( 2x + 6y = 1 ) (from the equation ( x + 3y = \frac{1}{2} ))
These are the equations that are in standard form.