Answer:
A D and E
Step-by-step explanation:
Part A:
23 + 13x ≤ 81
Part B:
23 + 13x ≤ 81
<u>-23 </u> <u>-23</u>
13x ≤ 58
<u>/13 </u> <u>/13</u>
x ≤ 4.46
Part C:
This means that you can have 4 cheeseburgers while keeping the fat under 81 grams.
Answer:
a ) y = 1 and x = -1
d) y = 5 and x = -1/2
Step-by-step explanation:
<h2><u>
Substitution method</u></h2><h2><u>Question a</u></h2>
y = x+ 2
y = 2x + 3
<em>we can make the first formula in terms of x , so we can place in into the second formula</em>
y = x + 2
x = y - 2
now put y - 2 where x is in the second equation
y = 2x + 3
y = 2(y - 2) + 3
y = 2y - 4 +3
now solve
4 - 3 = 2y -y
y = 1
since y = 1 we can find what x is by putting into the first formula
y = x +2
x = y - 2
x = (1) -2
x = -1
<h3><u>hence y = 1 and x = -1 </u></h3><h3><u /></h3><h2><u>Question d</u></h2>
y = 2x + 6
y = 4 - 2x
<em>we can make the first formula in terms of x , so we can place in into the second formula</em>
y = 2x + 6
y - 6 = 2x
x = (y-6)/ 2
now place (y-6)/2 where x is in the second formula
y = 4 -2x
y = 4 - 2 (
)
now solve
the multiplication by 2 and division by 2 are cancelled out
hence making the simplified equation as:
y = 4 - y + 6
2y = 4 + 6
2y = 10
y = 5
now place this into the first equation
y = 2x + 6
y - 6 = 2x
x = (y-6)/ 2
x = (5-6)/2
x = -1/2
<h3><u>
hence y = 5 and x = -1/2</u></h3>
Questions 1, 2, 3, and 4 are exercises to give you practice with
common denominators. For each of these questions, change all
the fractions to common denominators, and the answers jump out at you.
#1). 5/12 = 25/60
2/5 = 24/60
Make um negative, and then you'll have the answer right away.
#2). The one that's negative is obviously the least.
Both positive ones must be bigger than the negative one.
For the positive ones:
2/5 = 6/15
2/3 = 10/15 .
Now it's easy.
#3). This is tough. The least common denominator is 2,520 !
It's probably easier to just do the divisions and get the decimals
for each fraction.
-5/8 = -0.625
-7/9 = -0.777...
-4/5 = -0.8
-3/7 = -0.428...
Now it's easy to line um up.
#4). Sneaky one.
Look closely at each fraction.
B, C, and D are all less than 1, so they're not between 1 and anything more than 1.
8/5 is the only one that's more than 1.
#5). A fraction is just a short way to write a division problem.
When you see a fraction, it means
"the top number divided by the bottom number" .
When you actually do the division, the quotient you get
is the decimal form of the fraction.
To change a decimal into a percent,
move the decimal point two places that way ==> .
The numbers in the boxes at the bottom of #5 are the correct numbers,
but they both should be negative. (because the -3/8 is negative)
Answer:
-1/4
Step-by-step explanation:
4x - 15 = -16
4x = -1
x = -1/4
