Use u subsitution the solve by grouping
u=x^2
u^3-16u=4u^2-64
u^3-4u^2-16u+64=0
(u^3-4u^2)+(-16u+64)=0
u^2(u-4)+(-16)(u-4)=0
(u^2-16)(u-4)=0
(u-4)(u+4)(u-4)=0
(u+4)(u-4)^2=0
u=x^2
(x^2+4)(x^2-4)^2=0
(x^2+4)((x-2)(x+2))^2=0
(x^2+4)(x-2)²(x+2)²=0
set to zero
x^2+4=0
x^2=-4
x=+/-2i
x-2=0
x=2
x+2=0
x=-2
the other roots are -2 and 2
for graphinc calculator, graph and find x intercepts
First step of the equation is to simplify the equation 2a • b = a2 + b2 into 2 ab = a2 + b2. This cannot be factored anymore although. when we try to substitute a with 5 and b with 2, the answer in the right hand side of the equation is -9. hence the answer to this problem is false. we can try another values to verify.
Answer:
The only multiples of 3 between 20 and 30 are 21, 24, and 27. Only 27 satisfies the condition that it is 3 times the sum of its digits.
Step-by-step explanation:
There you goo, hope it helped you:)