Question

5х-3у, если: х=12 2/5, у=9 2/3

Answer 1

5х-3у
5×12 2/5-3×9 2/3
5×62/5-3×29/3
310/5-87/3
930/15-435/15=495/15=33

Answer 2

To evaluate the expression 5x - 3y, where x = 12 2/5 and y = 9 2/3, we need to convert the mixed numbers to improper fractions and substitute the values into the expression.

Converting x and y to improper fractions: x = 12 2/5 = (5 * 12 + 2) / 5 = 62/5 y = 9 2/3 = (3 * 9 + 2) / 3 = 29/3

Now, substituting the values into the expression: 5x - 3y = 5(62/5) - 3(29/3)

Multiplying: 5x = 5 * 62/5 = 62 -3y = -3 * 29/3 = -87/3

Subtracting: 5x - 3y = 62 - 87/3

To subtract the fractions, we need a common denominator: 62 = 62/1 87/3 = 87/3 * 1/1 = 87/3

Now, with a common denominator of 3: 5x - 3y = 62/1 - 87/3

To subtract the fractions, we need the same denominator: 5x - 3y = (62 * 3)/(1 * 3) - 87/3

Multiplying: 5x - 3y = 186/3 - 87/3

Subtracting: 5x - 3y = (186 - 87)/3

Calculating: 5x - 3y = 99/3

Simplifying the fraction: 5x - 3y = 33

Therefore, the value of 5x - 3y, when x = 12 2/5 and y = 9 2/3, is 33.