Step-by-step explanation:
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For the first one multiply each term by the LCM of 4 and 6, which is 12:-
15x -36 = 2y..................(1)
and second multiply by 5:-
2x + y = 9..............(2)
solving:-
from equation (2) y = 9-2x, substitute in equation (1):-
15x - 36 = 2(9-2x) = 18 - 4x
19x = 54
x = 54/19 = 2.84
so y = 9 - 2(2.84) = 3.32
The value of x is 1.14 or x = -1.47
We find the value of x in the quadratic equation 3x^2 +x-5=0
Using the formula: (-b ± √ (b²- 4 a c)) / (2a)
Where the value of a = 3, b = 1 and c = -5
Substituting the above values (a = 3, b = 1 and c = -5)
in the formula:
(-1 ± √ (1²- 4 3 (-5))) / (2*3)
= (-1 ± √ (1+60)) / (6)
= (-1 ± √ (61)) / (6)
= (-1 ± 7.81) / (6)
= (-1 + 7.81) / (6) or (-1 -7.81) / (6)
= (6.81) / (6) or (-8.81) / (6)
=1.135 or -1.468
Hence the value of x= 1.14 or -1.47
LEARN MORE ABOUT QUADRATIC EQUATIONS HERE: brainly.com/question/1214333
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