<h2>
Answer:</h2>
- option (c) = -19 + x = -21
<h2>Step by step explanation:</h2>
<u>Question</u> : A number added to -19 is -21
<h3>
<u>Solution</u> ↓</h3>
First of all to make equation
Equation means LHS = RHS
For eg we take :-
50 - 20 = 10 + 20
30 = 30
Therefore, LHS = RHS
<h3>
According to the question :</h3>
- Which number would we add in -19 to get -21 and we get LHS = RHS
Make an equation
-19 + x = -21
x = -21 + 19
x = -2
Add -2 in the variable of x
Variable means any unknown value we used in maths. For eg :- x,y,z,a,b,c,p,q,r etc.
-19 + (-2) = -21
-19 - 2 = -21
-21 = -21
Therefore, LHS = RHS.
Answer:
No
Step-by-step explanation:
No because if it's 20,000 on 1 it should be 40,000 on 2 but its not so its not proportional
Answer:
11, 12, 13
Step-by-step explanation:
n, n + 1, n+2
sum is 36
Answer:
The equation is 
Step-by-step explanation:
Let the time for which i bike is = x hours
Let the distance traveled in x hours = y miles
Ratio of distance and time will be = x : y
I travel 11.2 miles in 1.4 hours then the ratio of time and the distance traveled will be 1.4 : 11.2 Or 14 : 112
then the ratio of distance and time will be same in both the cases
So equation will be

Hence, equation representing the proportional relationship will be 
Answer:
The value of y is unknown bas there is no equation