Advertisements
Advertisements
Question
Solve the following pairs of equations:
y - x = 0.8
`(13)/(2(x + y)) = 1`
Advertisements
Solution
The given equations are
y - x = 0.8
-x + y = 0.8 ....(i)
And, `(13)/(2(x + y)) = 1`
⇒ 13 = 2x + 2y
⇒ 2x + 2y = 13 ....(ii)
Multiplying eqn. (i) by 2, we get
-2x + 2y = 1.6 ....(iv)
Adding eqns. (ii) and (iii), we get
4y = 14.6
⇒ y = 3.65
Substituting the value of y in eqn. (i), we get
-x + 3.65 = 0.8
⇒ -x = -2.85
⇒ x = 2.85
Thus, the solution set is (2.85, 3.65).
APPEARS IN
RELATED QUESTIONS
For solving pair of equation, in this exercise use the method of elimination by equating coefficients:
y = 2x - 6; y = 0
If 10y = 7x - 4 and 12x + 18y = 1; find the values of 4x + 6y and 8y - x.
Solve the following simultaneous equation :
8v - 3u = 5uv
6v - 5u = -2uv
Solve the following pairs of equations:
`(2)/x + (3)/y = (9)/(xy)`
`(4)/x + (9)/y = (21)/(xy)`
Where x ≠ 0, y ≠ 0
Solve the following pairs of equations:
`(5)/(x + y) - (2)/(x - y)` = -1
`(15)/(x + y) + (7)/(x - y)` = 10.
`4x + 6/y = 15 and 6x - 8/y = 14.` Hence, find a if y = ax - 2.
Seven more than a 2-digit number is equal to two less than the number obtained by reversing the digits. The sum of the digits is 5. Find the number.
If 1 is added to the denominator of a fraction, the fraction becomes `(1)/(2)`. If 1 is added to the numerator of the fraction, the fraction becomes 1. Find the fraction.
9 pens and 5 pencils cost Rs.32, and 7 pens and 8 pencils cost Rs.29. Find the unit price for each pen and pencil.
Two mobiles S1 and S2 are sold for Rs. 10,490 making 4% profit on S1 and 6% on S2. If the two mobiles are sold for Rs.10,510, a profit of 6% is made on S1 and 4% on S2. Find the cost price of both the mobiles.
