Question

Solve the following equation by middle term factorisation and complete the square method 3 x square + 5 x - 28 equals to zero

Answer 1

Answer:

by middle term

3x²+5x-28

3x²+12x-7x-28

3x(x+4)-7(x+4)=0

(x+4)(3x-7)

x=-4 ,7/3

by completing

3x²+5x-28

divide by 3

x²+5x/3-28/3=0

x²+5x/3+(5/6)²=28/3+(5/6)²

(x+5/6)² = 361/36

x+5/6=19/6,-19/6

by taking +

x=19-5/6=7/3

by taking -

x=-19-5/6=-4