Step-by-step explanation:
4x + 8y = 40
4x + (8×0.8) = 40
4x + 6.4 = 40
4x = 33.6
4x÷4 = 33.6 ÷ 4
x = 8.4
Answer: 
Step-by-step explanation:
We can rewrite the left hand side as a perfect square, more specifically

So, taking the square root of both sides,

Ok its it is three hundred million seven hundred sixty three one hundred thirty six