7 Electricity prices increased by 66%
in 2009.
Mr and Mrs Smith's monthly bill
was £69.72 after the increase.
What was the bill before the
increase?

$23.7

Step-by-step explanation:

Electricity prices increased by 66% in 2009.

Mr and Mrs Smith’s bill was $69.72 after the increase .

The bill before the increase will be 66% / 100% x $69.72

= 0.66 x 69.72

= $46.02

Bill before the increase will be $69.72 - $46.02

=$23.7

the answer is 0.071

good luck! : d

answer:   x = 3 + √11     and     x = 3 - √11

step-by-step explanation:

x² - 6x + 9 = 11

(x - 3)² = 11

x - 3 = ±√11

    x = 3 ± √11

x = 3 + √11     and     x = 3 - √11