If 2x=1 , then x= ?
a) 0
b) 1
c) 2
d) None of these
Solution: If 2x= 1, 20= 1
So, 2x=20 x=0
What is the standard form of (x+7)(x-3)=-7
a) x2+4x-14= 0
b) x2-4x-14 = 0
c) x2+4x-12= 0
d) x2+4x+14 = 0
Solution:(x+7)(x-3)=-7
x2– 3x+7x – 21=-7
x2+4x – 21=-7
x2+4x – 21+7= 0
x2+4x – 14=0
What will be the solution set of x2-11x=152
a) {-8,19}
b) {8,-19}
c) {8,19}
d) {-8,-19}
Solution: x2– 11x=152
x2– 11x – 152=0
x2– 19x+8x – 152=0
x(x – 19)+8(x – 19)=0
(x – 19)(x+8)=0
x – 19=0 , (x+8)=0
x=19 , x=-8
What will be the solution set of x2-x-20=0
a) {-4,5}
b) {4,-5}
c){-2,5}
d) {4,5}
Solution:x2– x – 20=0
x2– 5x+4x – 20=0
x(x – 5)+4(x – 5)=0
(x-5)(x+4)=0
x – 5=0 , x+4=0
x=5 , x=-4
Which equation has exactly two solutions:
a) 2x+3=0
b) 2x=0
c) x-1=0
d) x2+2x +1=0
Solution:
x2+2x +1=0
x2+x+x+1=0
x(x+1)+1(x+1)=0
(x+1)(x+1)=0
x+1=0 , x+1=0
x=-1 , x=-1
