Question

Maths questions please solve it. ...​

Answer 1

Answer:

1. 3x(4x-5)+3=12x^2-15x+3=3(4x^2-5x+1)

for x=3, value of 3(4x^2-5x+1)

=3{4(3^2)-5(3)+1}

=3{4x9-5x3+1}

=3{36-15+1}

=3{22}=66

for x=1/2,value of 3(4x^2-5x+1)=

=3{4(1/2)^2-5(1/2)+1}

=3{4x1/4x2-5/2+1}

=3{2-5/2+1}

=3(1/2)=3/2

2. p(p-q)+9(q-p)+r(r-p)

p^2-pq+9q-9p+r^2-pr

=p^2+q^2-p(q+r)+9(q-p)

Answer 2

it may be helpful to you