Question

If x = 1/4 and Y = 3/7 evaluate the following expression 7x-4y ​

Answer 1

If x = 1/4 and Y = 3/7

Evaluate the following expression: 7x - 4y

`\\`

`\rm{7 ( (1)/(4)) - 4( (3)/(7) ) } \\`

• Substitute the given value of x and y

`\rm { \orange{7 * (1)/(4) }} - 4 * (3)/(7) \\`

• Calculate the product of the rational numbers

`\rm{ (7)/(4) - \orange{ 4 * (3)/(7 )} } \\`

• Calculate the product of the rational numbers

`\rm \orange{ (7)/(4) - (12)/(7) } \\`

• Find the difference between the two fractions

`= \small{\boxed{{\sf{ (1)/(28) }}}}`

Therefore, the answer is 1/28.

Answer 2

Explanation:

`\text{Substitute the values of x and y in the expression}`

`7x - 4y = 7*(1)/(4)-4*(3)/(7)`

`\sf =(7)/(4)-(12)/(7)\\\\ [LCM \ of 4 \ and \ 7 = 28]\\\\ =(7*7)/(4*7)-(12*4)/(7*4)\\\\=(49)/(28)-(48)/(28)\\\\=(1)/(28)`