Answer:
20 cm
Step-by-step explanation:
We can use ratios to solve
We know x = 7 since they are of equal length
x x+7
----- = -------
10 y
7 7+7
----- = -------
10 y
Using cross products
7y = 14*10
7y = 140
Divide by 7
7y/7 = 140/7
y = 20
In Step 6, the equation is ...
-12 = x - 36
In step 7, the equation is ...
-12 +36 = x -36 +36
Clearly, to get to step 7, 36 has been added to both sides of the equation.
Adding 36 to both sides of the equation is justified by ...
... C) Addition Property of Equality
_____
<em>More about the addition property of equality</em>
The addition property of equality says you can add the same value to both sides of an equation without changing the values of the variables that make the equation true. Here, x=24 makes the equation of step 6 true, and x=24 makes the equation of step 7 true.
We assume the two numbers are x and (x+1)
so x^2+(x+1)^2=421
x^2+(x^2+2x+1)=421
2x^2+2x-420=0
According to the formula of quadratic
x=14 or-15
cuz we know the two numbers are integers
so x=14
therefore the other number is 15
To make sure that's correct
14^2+15^2=421
Hope that helps you!!
