Write the factors of the quadratic equation: x^2 -4x-21=0

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

Step-by-step explanation:

To factorise the quadratic

Consider the factors of the constant term (- 21) which sum to give the coefficient of the x- term (- 4)

The factors are - 7 and + 3, since

- 7 × 3 = - 21 and - 7 + 3 = - 4, thus

(x - 7)(x + 3) = 0 ← in factored form

infinitely many solutions

step-by-step explanation:

we have been given the equation;

2(2x + 3) = -4 + 2(2x + 5)

we need to determine the value of x.

2(2x + 3), we expand this expression to obtain 4x + 6

similarly 2(2x + 5) will become 4x + 10

now we have;

4x + 6 = -4 + 4x + 10

4x + 6 = 4x + 10 - 4

4x + 6 = 4x + 6

the expression on the left hand side is identical to the one on the right hand side. therefore, we are looking at just a single straight line whose equation is;

y = 4x + 6

consequently, we shall have infinitely many solutions