Question

if 2x+y=23 and 4x-y=19;find the value of x-3y and 5y-2x.

Answer 1

2x+y = 23......(i)4x−y = 19.....(ii)
Adding both (i) and (ii) we get;
2x+y+4x−y = 23+19⇒6x = 42⇒x = 426 = 7
Putting the value of x in (i) we get;
2×7+y = 23⇒14+y = 23⇒y = 23−14 = 9
So the value of x - 3y is given by;
x−3y=7−3×9 = 7−27 = −20
And the value of 5y - 2x is given by;
5y−2x = 5×9−2×7 = 45−14

Answer 2

Heya
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2x+y=23. .....(1)
4x-y=19. ......(2)

adding (1) and (2)
2x+y=23
+ 4x-y=19
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6x=4
x=7
Now Putting x=7 in (2)
4x-y=19
4×7-y=19
28-y=19
y=28-19
y=9
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So,
x-3y=7-3×9
=7-27
x-3y=-20

Again,
5y-2x=5×9-2×7
=45-14
5y-2x=31
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Finally answers received ,I hope it helps you.