It is given that
a+b=20 -------------------- (1)
b+c=30 -----------------------(2)
We have to calculate
3 a + 4 b +7 c
Now multiplying equation(1 )by 3,we get
3 a+ 3 b=60 ----------------------------------(3)
and Multiplying equation( 2) by 4,we get
4 b + 4 c=120 -----------------------------------(4)
Adding expression (3) and (4),we get i.e left hand side of 3 to left hand side of 4 and right hand side of 3 to right hand side of 4.
3 a+ 3 b+ 4 b+ 4 c=60+120
Adding like terms, we get
3 a+ 7 b+ 4 c =180, Which is the required solution.
Answer:
yes, 1 can never equal 2 unless it is manipulated (ex: 1(2) = 2)
because one is not being manipulated to equal 2 here, it is a false statement and will always be a false statement.
For this case we have the following system of equations:
We solve by the substitution method:
We substitute the first equation in the second equation:
We apply distributive property considering that 
We subtract 69 from both sides of the equation:
We divide by 8 on both sides of the equation:
We look for the value of the variable y:
Thus, the solution of the system is 
Answer:
Answer:
Domain:- All real numbers
Range:-[3,infinite)
Step-by-step explanation:
In the function there's no value of x for which it is not defined thus domain is R.
Now a modulus will have always it's minimum value 0 thus minimum value of function is 0+3=3. And Max value of a modulus is infinite so infinite+3=infinite.
