Answer:
Year 10 Interactive Maths - Second Edition
Problem Solving
Linear equations are often used to solve practical problems that have an unknown quantity. We use a suitable pronumeral to represent the unknown quantity, translate the information given in the problem into an equation, and then solve the equation using the skills acquired earlier in this chapter.
Example 11
If a number is increased by 8, the result is 25. Find the number.
Solution:
Let x be the number. Increasing x by 8 gives x + 8, which we are told is 25. Therefore, x + 8 = 25. Subtract 8 from both sides to find x = 17. So, the number is 17.
Step-by-step explanation:
I hope this helps!!!
Answer:
144°
Step-by-step explanation:
The sum of the interior angles of a polygon is
sum = 180° × (n - 2) ← n is the number of sides
Here n = 8 ( octagon ), hence
sum = 180° × 6 = 1080°
let the measure of 1 congruent angle be x
Then sum the 8 angles and equate to 1080
100 + 120 + 140 + 5x = 1080
360 + 5x = 1080 ( subtract 360 from both sides )
5x = 720 ( divide both sides by 5 )
x = 144
Thus each of the 5 congruent angles is 144°
The number used for the interest rate will be 6.17% in decimal form: 0.0617.
