Let f and b be the cost of foil and batteries respectively. We are first given that:
2f+3b=21 subtract 3b from both sides
2f=21-3b divide both sides by 2
f=(21-3b)/2
Then we are given:
5f+2b=25, using f found above in this equation gives you:
5(21-3b)/2+2b=25
(5(21-3b)+4b)/2=25 multiply both sides by 2
5(21-3b)+4b=50 carry out indicated operations on left side
105-15b+4b=50 combine like terms on left side
105-11b=50 subtract 105 from both sides
-11b=-55 divide both sides by -11
b=5, since f=(21-3b)/2
f=(21-3*5)/2
f=3
So batteries cost $5 and foil cost $3.
Answer:
Never
Step-by-step explanation:
Pi is a an irrational number. Multiply any rational number by pi and you will never get a rational number. The answer is never
Answer:
I'm sure there might be a typo in the question (AKA the slope is -5/2)
but the answer would be
D
Step-by-step explanation:
y= mx+ b
where m is the slope, and b is the y intercept
y= -52x -2
..........
5x + 2y = –4
2y= -5x -4
y= - 5/2x -2
Answer:
17. x = y^2 - 2ay +a^2
18. x = y^2 - a
Step-by-step explanation:
17. Since we want to make x the subject of the formula, we first isolate the square root of x and get
= y - a.
squaring both sides,
x = y^2 - 2ay +a^2
18. Since both x and the a are under the square root, we first start by squaring both sides.
So y^2 = x+a.
Isolating the x, we get
x = y^2 - a
Answer:
3
Step-by-step explanation:
The sum of these two polynomials is - 2 x^2 - 3. the two x variables are additive inverses and -6 x^2 and 4 x^2 equal - 2 x^2 and -3 results from -4 and 1
Multiplying the sum by 2 gives us - 4 x^2 - 6 . Answer 3
