Question

Marcus solved for x in the quadratic equation x2 – 10x + 25 = 0.

Answer 1

1 ,3 and 4 are correct :)

Answer 2

Option 1,3 and 4 are correct.

Explanation:

Given is a quadratic equation

`x^2-10x+25=0`

Marcus used quadratic formula to solve this

The correct use of formula is

`(-b+/√(b^2-4ac) )/(2a)`

for the quadratic equation
`ax^2+bx+c=0`

Comparing we have a =1, b =-10: c=25

The student should have substituted -10 for b but he wrong did only 10

II option is wrong since 2 is substituted correctly

III option is right -4ac i.e. the product x 4 must have been subtracted

IV option is right since repeated root is there so only one solution