Question

5. Solve each equation by systematic trial.

a) x-68=192
b) g+33=251
c) 3z-16=74
d) 15h+9=84

Answer 1

a) x = 260

b) g = 218

c) z = 30

d) h = 5

Explanation:

a)
`x-68=192`

Predict a number; let's say x = 225

`225-68=192\\157=192`

Too low; try with a higher number; let's say x = 270

`270-68=192\\202=192`

Too high, we're closer.

x = 260

`260-68=192\\192=192`

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b)
`g+33=251`

let's say g = 230

`230+33=251\\263=251`

Too high. Try g = 221

`221+33=251\\254=251`

We're almost there. Let's try with g = 218

`218+33=251\\251=251`

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c)
`3z-16=74`

Let's try with z = 15

`3(15)-16=74\\45-16=74\\29=74`

Too low; try a higher number. z = 30

`3(30)-16=74\\90-16=74\\74=74`

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d)
`15h+9=84`

Let's try with h = 6

`15(6)+9=84\\90+9=84\\99=84`

Too high; let's try with h = 5

`15(5)+9=84\\75+9=84\\84=84`