Answer:

Step-by-step explanation:
The given expression is:

We expand the parenthesis using the distributive property to obtain;

Recall that;

We apply this property and multiply out the constant terms to obtain;

The pattern will be at the same place at 2 feet, 4 feet, 6 feet, 8 feet, 10 feet, 12 feet, 14 feet, 16 feet, and 18 feet
Answer:
v=2-2root7, v=2+2root7
Step-by-step explanation:
-2v+8(1+2v)=-90
-2-4v^2+8+16v=-90
6-4v^2+16v=-90
-4v^2+16v=-96
v=2-2root7, v=2+2root7
The energy of a photon is given by
E = h × v
where:
E is the energy in joules/photon
'h' is the constant 6.63 × 10⁻³⁴
'v' is the frequency 7.55 × 10¹⁴
Substitute 'h' and 'v' into the formula we have
E = (6.63×10⁻³⁴) × (7.55×10¹⁴)
E = (6.63×7.55) × (10⁻³⁴ × 10¹⁴)
E = 50.0565 × 10⁽⁻³⁴⁺¹⁴⁾
E = 50 × 10⁻²⁰ joules/photon