Advertisements
Advertisements
प्रश्न
If 2x + y = 23 and 4x - y = 19 : find the value of x - 3y and 5y - 2x.
Advertisements
उत्तर
2x + y = 23 ........(1)
4x - y = 19 ........(2)
Adding (1) and (2),
6x = 42
⇒ x = 7
∴ y = 23 - 2x
= 23 - 14
= 9
∴ x - 3y
= 7 - 3(9)
= 7 - 27
= -20
5y - 2x
= 5(9) - 2(7)
= 45 - 14
= 31.
APPEARS IN
संबंधित प्रश्न
For solving pair of equation, in this exercise use the method of elimination by equating coefficients :
13x+ 11y = 70
11x + 13y = 74
Find the value of m, if x = 2, y = 1 is a solution of the equation 2x + 3y = m.
Solve :
11(x - 5) + 10(y - 2) + 54 = 0
7(2x - 1) + 9(3y - 1) = 25
Solve :
`4x + [ x - y ]/8 = 17`
`2y + x - [ 5y + 2 ]/3 = 2`
Solve the following simultaneous equations:
13a - 11b = 70
11a - 13b = 74
The length of a rectangle is twice its width. If its perimeter is 30 units, find its dimensions.
The sum of the numerator and denominator of a fraction is 12. If the denominator is increased by 3, the fraction becomes `(1)/(2)`. Find the fraction.
Anil and Sunita have incomes in the ratio 3 : 5. If they spend in the ratio 1 : 3, each saves T 5000. Find the income of each.
A person goes 8 km downstream in 40 minutes and returns in 1 hour. Determine the speed of the person in still water and the speed of the stream.
A and B can build a wall in `6(2)/(3)` days. If A's one day work is `1(1)/(4)` of one day work of B, find in 4 how many days A and B alone can build the wall.
