Advertisements
Advertisements
प्रश्न
Solve for x and y:
0.4x + 0.3y = 1.7, 0.7x – 0.2y = 0.8.
उत्तर
The given system of equations is
0.4x + 0.3y = 1.7 …….(i)
0.7x – 0.2y = 0.8 …….(ii)
Multiplying (i) by 0.2 and (ii) by 0.3 and adding them, we get
0.8x + 2.1x = 3.4 + 2.4
⇒2.9x = 5.8
⇒x = `(5.8)/(2.9)` = 2
Now, substituting x = 2 in (i), we have
0.4 × 2 + 0.3y = 1.7
⇒0.3y = 1.7 – 0.8
⇒y = `(0.9)/(0.3)` = 3
Hence, x = 2 and y = 3.
APPEARS IN
संबंधित प्रश्न
Solve for x and y:
2x - 3y = 13, 7x - 2y = 20
Solve for x and y:
0.3x + 0.5y = 0.5, 0.5x + 0.7y = 0.74
Solve for x and y:
4x + 6y = 3xy, 8x + 9y = 5xy
Solve for x and y:
71x + 37y = 253, 37x + 71y = 287
Find the values of a and b for which the system of linear equations has an infinite number of solutions:
2x + 3y = 7, (a + b)x + (2a - b)y = 21.
Five years hence, a man’s age will be three times the sum of the ages of his son. Five years ago, the man was seven times as old as his son. Find their present ages
On selling a tea-set at 5% loss and a lemon-set at 15% gain, a shopkeeper gains Rs. 7. However, if he sells the tea-set at 5% gain and the lemon-set at 10% gain, he gains Rs. 14. Find the price of the tea-set and that of the lemon-set paid by the shopkeeper.
Find the value of k for which the system of equations 3x + 5y = 0 and kx + 10y = 0 has infinite nonzero solutions.
Find the value of k for which the following pair of linear equations has infinitely many solutions.
2x + 3y = 7, (k +1) x+ (2k -1) y = 4k + 1
If 17x + 15y = 11 and 15x + 17y = 21, then find the value of x − y.