Question

What is the solution to the equation |10-5y| =20

a) y=2
b) y=4
c) y=6
d) y=10

Answer 1

The correct answer is option c) y = 6

Explanation:

It is given that|10-5y| =20

Check each option

a) y = 2

|10 - 5y| = |10 - 5 * 2| = | 10 - 10 | = 0 ≠ 20

b) y = 4

|10 - 5y| = |10 - 5 * 4| = | 10 - 20 | = |-10| = 10 ≠ 20

c) y = 6

|10 - 5y| = |10 - 5 * 6| = | 10 - 30 | = |-20| = 20

d) y = 10

|10 - 5y| = |10 - 5 * 10| = | 10 - 50 | = |-40| ≠ 20

From the above result we get the correct answer is option c) y = 6

Answer 2

The correct answer option is a) y =2.

Explanation:

We are given the following equation and we are to find its solution:

`| 1 0 - 5 y | = 2 0`

Since the expression
`10-5y` is enclosed in a modulus, it means that its value cannot be negative, it has to be positive always.

`1 0 - 5 y = 2 0`

`-5 y = 2 0 - 1 0`

`-5 y = 1 0`

Ignoring the negative sign because of mod.

`y=(10)/(5)`

y = 2