Solve for an unknown value in a proportion using cross-multiplication.
All inputs must be valid numbers. 'a' cannot be zero.
Cross-multiplication is a mathematical method used to solve an equation between two fractions or ratios. It is based on the property that if two ratios are equal, their cross-products are also equal.
This technique is widely used in solving proportions, unit conversions, and finding unknown values in similar triangles or scale models.
Cross-multiplying gives: a * x = b * c. Solving for x gives the formula above.
Solve for x: 2/4 = 3/x
1. Cross-multiply: 2 * x = 4 * 3
2. Simplify: 2x = 12
3. Solve: x = 12 / 2 = 6
Final Answer: x = 6
Yes. The logic is the same: multiply the two known values that are diagonal to each other, and divide by the third known value.
If 'a' is zero, the proportion is undefined because you cannot divide by zero.
In the context of fractions, they are often used interchangeably. In vector calculus, however, 'cross product' refers to a specific vector operation.
It's used for scaling recipes, calculating currency exchange, determining travel time based on speed, and resizing images while maintaining aspect ratio.
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