Which equation is written in standard form?

Which equation is written in standard form?

• A. a(b + c) = ab + ac
• B. y - y1 = m(x - x1)
• C. Ax + By = C
• D. y = mx + b

Answer: (C)

Standard form for a linear equation puts the x- and y-terms on the left with a constant on the right: Ax + By = C, where A, B, and C are numbers (often integers) and there are no fractions, with both variables appearing on one side. The equation written as Ax + By = C fits this exactly, so it is in standard form. The other options represent different ways of writing a line: one expands a product, another uses point-slope form, and the last is slope-intercept form where y is isolated as y = mx + b. If you start from slope-intercept form and move terms to the left, you can get something like mx − y = −b, which is still Ax + By = C in standard form.

Standard form for a linear equation puts the x- and y-terms on the left with a constant on the right: Ax + By = C, where A, B, and C are numbers (often integers) and there are no fractions, with both variables appearing on one side.

The equation written as Ax + By = C fits this exactly, so it is in standard form. The other options represent different ways of writing a line: one expands a product, another uses point-slope form, and the last is slope-intercept form where y is isolated as y = mx + b. If you start from slope-intercept form and move terms to the left, you can get something like mx − y = −b, which is still Ax + By = C in standard form.