To solve this system by substitution, we must substitute in the value we are given for x in terms of y (the first equation) into the second equation. This is modeled below:
x = -8y - 15
2x + 5y = -8
2 (-8y - 15) + 5y = -8
Now, we should solve this new equation for y. To begin, we should use the distributive property to get rid of the parentheses on the left side of the equation and begin the simplification process.
-16y - 30 + 5y = -8
Next, we can combine like terms on the left side of the equation by adding together the two terms that both contain the variable y.
-11y - 30 = -8
Next, we should add 30 to both sides in order to move all of the constant (number) terms to the left side of the equation.
-11y = 22
After that, we should divide both sides of the equation by -11 in order to get the variable y alone.
y = -2
Now, we can substitute our value for y back into one of our original equations (it doesn't matter which one you choose; they will yield the same answer).
x = -8y - 15
x = -8(-2) - 15
To simplify, we should following the order of operations outlined by PEMDAS and compute the multiplication and then the subtraction.
x = 16 - 15
x = 1
Therefore, the answer to the system is x = 1 and y = -2, or (1,-2) when written as an ordered pair.
Hope this helps!
Answer:
No
Step-by-step explanation:
This is from a website so you might have to rephrase it but Direct variation describes a simple relationship between two variables . We say y varies directly with x (or as x , in some textbooks) if:
y=kx
for some constant k , called the constant of variation or constant of proportionality . (Some textbooks describe direct variation by saying " y varies directly as x ", " y varies proportionally as x ", or " y is directly proportional to x .")
This means that as x increases, y increases and as x decreases, y decreases—and that the ratio between them always stays the same.
The graph of the direct variation equation is a straight line through the origin.
Answer:
3x + x + 3x + x = 360
8x = 360
x = 45
3(45)= 135
Step-by-step explanation:
Answer:
Ambitious
Answer
Find out the what is the percentage of this discount .
To prove
Formula
Discount = Marked price - selling price
As given
a jar of natural peanut butter normally costs $4.00 .
it's on sale for $3.60 .
thus
Marked price = $4.00
selling price = $3.60
put in the above formula
Discount = 4.00 - 3.60
= 0.4
Formula
put the value
Discount percentage = 10%
Option (a) is correct .
Hence proved