4+3x the (x has an exponent of 4)=81

x = 2.25 (Approximately)

Step-by-step explanation:

4 + 3x^4 = 81

4 - 4 + 3x^4 = 81 - 4

3x^4 = 77

(3x^4)/3 = 77/3

x^4 = 25.67 (Approximately)

x = 2.25 (Approximately)

it's equivalent, so we can say that its equal.

let's call the denominator x and the numerador is 18 less then denominator, x - 18.

multiply

2.x = 5.(x - 18)

2x = 5x - 90

90 = 5x - 2x

90 = 3x

x = 90/3

x = 30

so: