If ( x - 1 ) * ( x + 3 ) = 0 => x = 1 or x = -3;
But, (x-1)(x+3)=1 => x^2 + 3x -x - 3 = 1 => x^2 + 2x - 4 = 0;the discriminant is 2^2 - 4 * 1 * ( -4 ) = 20 => the solutions are x1 =
( - 2 +

) / 2 ; x2 = - 2 -

) / 2;
It’s a and c my good friend
Im so confused about this question
From the diagram:
AB + BC = AC
we know that AC = 42, therefore:
AB + BC = 42 ..............> equation I
We know that the ratio AB:BC is 3:4. This means that:
AB/BC = 3/4
4AB = 3BC
AB = (3/4) BC ...............> equation II
Substitute by equation II in equation I to get BC as follows:
(3/4) BC + BC = 42
1.75 BC = 42
BC = 24Substitute with the value of BC in equation II to get AB as follows:
AB = (3/4) * 24 = 18