Advertisements
Advertisements
प्रश्न
Solve the following pairs of linear (simultaneous) equation using method of elimination by substitution:
`x/6 + y/15 = 4`
`x/3 - y/12 = 4 3/4`
उत्तर
`x/6 + y/15 = 4`
⇒ `[ 5x + 2y ]/30 = 4`
⇒ 5x + 2y = 120
⇒ 5x = 120 - 2y
⇒ x = `[ 120 - 2y ]/5` ....(1)
And,
`x/3 - y/12 = 4 3/4`
⇒ `1/3( x - y/4 ) = 19/4`
⇒ `1/3([120 - 2y]/5 - y/4 ) = 19/4`
⇒ `[ 480 - 8y - 5y ]/20 = 57/4`
⇒ `[ 480 - 13y ]/20 = 57/4`
⇒ 480 - 13y = 285
⇒ 13y = 195
⇒ y = 15
Substituting the value of y in (1), we have
`x = [ 120 - 2 xx 15]/5 = [120 - 30]/5 = 90/5 = 18`
∴ Solution is x = 18 and y = 15
APPEARS IN
संबंधित प्रश्न
Solve the following pair of linear (Simultaneous ) equation using method of elimination by substitution :
2( x - 3 ) + 3( y - 5 ) = 0
5( x - 1 ) + 4( y - 4 ) = 0
Solve the following pair of linear (simultaneous) equation using method of elimination by substitution:
3x + 2y =11
2x - 3y + 10 = 0
Solve the following pair of linear (simultaneous) equation using method of elimination by substitution :
2x - 3y + 6 = 0
2x + 3y - 18 = 0
Solve th following pair of linear (Simultaneous ) equation using method of elimination by substitution :
`[ 2x + 1]/7 + [5y - 3]/3 = 12`
`[3x + 2 ]/2 - [4y + 3]/9 = 13`
Solve the following simultaneous equations by the substitution method:
5x + 4y - 23 = 0
x + 9 = 6y
Solve the following simultaneous equations by the substitution method:
2x + 3y = 31
5x - 4 = 3y
Solve the following simultaneous equations by the substitution method:
7x - 3y = 31
9x - 5y = 41
Solve the following simultaneous equations by the substitution method:
3 - (x + 5) = y + 2
2(x + y) = 10 + 2y
Solve the following simultaneous equations by the substitution method:
7(y + 3) - 2(x + 2) = 14
4(y - 2) + 3(x - 3) = 2
The difference of two numbers is 3, and the sum of three times the larger one and twice the smaller one is 19. Find the two numbers.
If a number is thrice the other and their sum is 68, find the numbers.
The sum of four times the first number and three times the second number is 15. The difference of three times the first number and twice the second number is 7. Find the numbers.
The age of the father is seven times the age of the son. Ten years later, the age of the father will be thrice the age of the son. Find their present ages.
A father's age is three times the age of his child. After 12 years, twice the age of father will be 36 more than thrice the age of his child. Find his present age.
* Question modified
In a ABC, ∠A = x°, ∠B = (2x - 30)°, ∠C = y° and also, ∠A + ∠B = one right angle. Find the angles. Also, state the type of this triangle.
Solve by the method of elimination
13x + 11y = 70, 11x + 13y = 74
The monthly income of A and B are in the ratio 3 : 4 and their monthly expenditures are in the ratio 5 : 7. If each saves ₹ 5,000 per month, find the monthly income of each
