Eva is working out the area of the triangle. The base is 7.8 cm and the length of one side is 6.3 cm. I multiply and then divide by 2. What mistake has Eva made?

Eva multiplied by two, and not 1/2.

Step-by-step explanation:

To find the area of a triangle, you must multiply the base and the height by 1/2.

Height: 6.3cm

Base: 7.8cm

1/2×6.3×7.8= 24.57

since your problem is x^4 = 81, what you have to undeo is the "to the fourth power" part.

the inverse (opposite operation) of "to the fourth power" is "to the fourth root".

  (x^4) ^ ¼   = 81 ^ ¼  

  81 = 3^4     so (3 ^ 4) ^ ¼   =   3 ^ 1   = 3

by hand: (3 ^ 4) ^ ¼   =   3 ^ (4 x ¼) = 3 ^ 1   = 3   (when you take a power to a power, multiply the exponents.)

or, do it by calculator. one way of finding the fourth root is to use ^ (1/4)

step-by-step explanation:

b

step-by-step explanation:

the word superfluous means unnecessary