Answer:
Step-by-step explanation:
The number is x
it is negative
the square is 28 more than 3 times itself
x²=28+3x
minus (28+3x)
x²-3x-28=0
factor
(x-7)(x+4)=0
set to zero
x-7=0
x=7
this is not the answer because we were told the number was negative
x+4=0
x=-4
correct
the number is -4
test
(-4)²=28+3(-4)
16=28-12
16=16
check
the number is -4
Given the function h(x)=x^2+14x+41, to solve by completing square we procced as follows;
x^2+14x+41=0
x^2+14x=-41
but;
c=(b/2)^2
and b=14
hence;
c=(14/2)^2=49
substituting the value of c in the expression we get:
x^2+14x+49=-41+49
x^2+14x+49=8
(x+7)^2=8
this can be written in vertex form;
h(x)=a(x-h)^2+k
where:
(h,k) is the vertex;
thus
(x+7)^2=8
h(x)=(x+7)^2-8
hence the vertex will be at the point:
(-7,-8)
to put them together and add them.
