Brass is made up of copper and zinc. every 100 grams of brass contains 20 grams of zinc. a) work out the weight of zinc in 60 grams of brass. brass contains 4 parts by weight of copper to 1 part by weight of zinc. b) work out the weight of copper in 350 grams of brass.

The Discriminant = b²-4ac
1.
a=2
b= 5
c=-3
The Discriminant is 49
When a, b and c are real numbers, a ≠ 0 and discriminant is positive and perfect square, then the roots α and β of the quadratic equation ax2 + bx + c = 0 are real, rational unequal.

2.
a=-1
b=1
c=1
The Discriminant is 5
When a, b and c are real numbers, a ≠ 0 and discriminant is positive but not a perfect square then the roots of the quadratic equation ax2 + bx + c = 0 are real, irrational and unequal.

3.
a=1
b=6
c=11
The Discriminant is-8
then the roots α and β of the quadratic equation ax2 + bx + c = 0 are unequal and imaginary.

4.
a=9
b=-54
c=81
The Discriminant is 0
the roots α and β of the quadratic equation ax2 + bx + c = 0 are real and equal.