Let's solve your system by substitution.
y
=
−
2
x
+
7
;
y
=
5
x
−
7
Step: Solve
y
=
−
2
x
+
7
for y:
y
=
−
2
x
+
7
Step: Substitute
−
2
x
+
7
for
y
in
y
=
5
x
−
7
:
y
=
5
x
−
7
−
2
x
+
7
=
5
x
−
7
−
2
x
+
7
+
−
5
x
=
5
x
−
7
+
−
5
x
(Add -5x to both sides)
−
7
x
+
7
=
−
7
−
7
x
+
7
+
−
7
=
−
7
+
−
7
(Add -7 to both sides)
−
7
x
=
−
14
−
7
x
−
7
=
−
14
−
7
(Divide both sides by -7)
x
=
2
Step: Substitute
2
for
x
in
y
=
−
2
x
+
7
:
y
=
−
2
x
+
7
y
=
(
−
2
)
(
2
)
+
7
y
=
3
(Simplify both sides of the equation)
Answer: x=2 and y=3
Answer:
Step-by-step explanation:
We require 2 equations with the repeating digits (63) placed after the decimal point.
let x = 0.636363..... (1) multiply both sides by 100
100x = 63.6363... (2)
Subtract (1) from (2) thus eliminating the repeating digits
99x = 63 ( divide both sides by 99 )
x = = ← in simplest form
Answer:
Yes, x and y have a proportional relationship.
Step-by-step explanation:
A proportional relationship means that, when comparing two quanities, that they are both changing at a constant (same) amount. When looking at a table to compare quantities, you can see that the pounds of tomatoes 'x' is increasing by one (1) each time. If you look at the amount spent in dollars 'y', you can see that for each pound (x), the cost is increasing by $4. So, since for every pound of tomatoes that is purchased increases by $4, then their relationship is proportional.
Step-by-step explanation:
iwij edge hnenennenenenebdbd dbbdbdnndnd ndndndnndndnndndnndndnfnndnndndnr
Answer:
Mean = 528 ppm
Standard deviation = 90.8 ppm
Step-by-step explanation:
Assuming a basis of 100 trees
6 trees with 350 ppm (minimal growth)
10 trees with 450 ppm (slow growth)
47 trees with 550 ppm (moderate growth)
37 trees with 650 ppm (rapid growth)
Mean = xbar = Σx/N
x = each variable
xbar = mean
N = number of variables = 100
Σx = sum of all variables = sum of all the ppm = (6×350) + (10×450) + (47×550) + (37×550) = 52800
xbar = 52800/100 = 528 ppm
Standard deviation = σ = √[Σ(x - xbar)²/N]
x = each variable
xbar = mean = 528
N = number of variables = 12
Σ(x - xbar)² = [6(350 - 528)²] + [10(450 - 528)²] + [47(550 - 528)²] + [37(650 - 528)²] = 824400
σ = √[Σ(x - xbar)²/N] = √(824400/100) = 90.8 ppm