Answer:
4 goats
Step-by-step explanation:
Let us represent
Number of quails = x
Number of goats = y
Quails have 2 legs
Goats have 4 legs
Hence:
There are 6 animals in the pen some are quails and some are goats
x + y = 6...... Equation 1
x = 6 - y
if there are 20 legs in all how many quails
2x + 4y = 20..... Equation 2
We substitute 6 - y for x in Equation 2
2(6 - y) + 4y = 20
12 - 2y + 4y = 20
Collect like terms
- 2y + 4y = 20 - 12
2y = 8
y = 8/2
y = 4 goats
The number of goats there are 4 goats
So the problem has no symbols, but we're going to multiply because the fraction on the left is right next to the parentheses.
-5/2 * 1/10x = -5x/20
I put "x" next to the 5 because the "x" counts as part of the numerator. Now that it's 5x over 20 that equals one, I'd first reduce -5x/20 into -x/4, then do
-x/4 * -4 = 1 * -4
To make the "x" side equal one, we have to multiply both sides by -4, to make both sides equal.
x = -4.
Answer: 42 cm3
Step-by-step explanation:
Solution: The missing reason in Step 8 is substitution of
.
Explanation:
The given steps are used to prove the formula for law of cosines.
From step 5 it is noticed that our equation is
..... (1)
From step 7 it is noticed that the value of
is
.
So by substituting
for
in equation (1) we get the equation of step 8, i.e.,

Hence, the missing reason in Step 8 is substitution of
.