Question

Draw the graph of the polynomial $x^{2} +3x-4$ and justify the proof............5 marks question

Answer 1

x^2 + 3x - 4
= x^2 - x + 4x - 4
=x(x-1) + 4(x-1)
=(x+4)(x-1)

Thus the roots of the equation are -4 and 1.
Here, a = 1 > 0

Thus the graph of the polynomial will be (See the attachment)

Answer 2

[tex] x^{2} +3x-4=0 \\ x^{2} +3x=4 \\ x^{2} +3x+2.25=4+2.25=6.25 \\ ( x+1.5) ^{2}=6.25 \\ x+1.5=+2.5 or -2.5 x= -4 or 1[/tex]