To find the x intercept set y = 0
x^2 + x - 2 =0
(x+2)(x-1) = 0
x = -2 , x = 1
When ever you have percentages, it should be helpful to bear in mind you can express them as multipliers. In this case, it will be helpful.
So, if we let:
a = test score
b = target score
then, using the information given:
a = 1.1b + 1
a = 1.15b - 3
and we get simultaneous equations.
'1.1' and '1.15' are the multipliers that I got using the percentages. Multiplying a value by 1.1 is the equivalent of increasing the value by 10%. If you multiplied it by 0.1 (which is the same as dividing by 10), you would get just 10% of the value.
Back to the simultaneous equations, we can just solve them now:
There are a number of ways to do this but I will use my preferred method:
Rearrange to express in terms of b:
a = 1.1b + 1
then b = (a - 1)/1.1
a = 1.15b - 3
then b = (a + 3)/1.15
Since they are both equal to b, they are of the same value so we can set them equal to each other and solve for a:
(a - 1)/1.1 = (a + 3)/1.15
1.15 * (a - 1) = 1.1 * (a + 3)
1.15a - 1.15 = 1.1a + 3.3
0.05a = 4.45
a = 89
The radius is half the diameter, so the formula would be r=d divided by 2
Answer:
Step-by-step explanation:
apply the indices law
- multiple means addition
- division means subtraction
- you are suppose to add the powers or subtract where necessary
- 4^9x 4^3= 4^5
- 6^5x6^2=6^7
- 8^6÷8=8^5
- 7^8÷7^6=7^2
Answer:
C = 25 + 3n
Step-by-step explanation:
Andre has a summer job selling magazine subscriptions.
We are told that:
Andy earns $25 per week plus $3 for every subscription he sells.
Let us represent
C = Total amount of money he makes this week
n = the number of magazine subscriptions Andre sells this week.
Hence, Our Algebraic expression =
C = $25 + $3 × n
C = 25 + 3n