4(2x-3)=6x+2
Please can someone give me the working out and answer?

The roots are

x=±√3,1±√6i

Step-by-step explanation:

(x2+a)(x2bx+c)=0

Multiply the two quadratics.

x4+bx3+(a+c)x2+abx+ac=0

Comparing terms gives.

b=−2,a+c=4,ab=6,ac=−21

We have

b=−2, ab=6

means that

a=−3.

now:

a+c=4 means c=7.

Verify with the last term

ac=−3⋅7=−21.

So the equation factorises to.

(x2−3)(x2−2x+7)=0

Factorise each term to give the roots.

x2−3=0, is x2=3, roots x=±√3x2−2x+7=0

complete the square

(x−1)2=−6

gives complex roots

x=±√6i

i leave the calculator work to you.

7. diameter 4 miles, circumference 4π miles

8. radius 0.2 miles, circumference 0.4π miles

[this is a bad problem because the actual radius of a car on the track is less than 0.2 miles so the answer is less than 0.4π miles]

9. radius 6 feet, circumference 12π feet

10. diameter 14 cm, circumference 14π cm

11. diameter 4.8 feet, circumference 4.8π feet

5x+2x=49

7x=49

x=7. 35 apples