This is a system of equations problem.
Blueberry = X, blackberry = Y
Joe:
5x + 10y = 135
James:
x + 9y = 104
Let’s isolate x from James’ equation.
x = 104 - 9y
Now substitute that into the first equation.
5(104 - 9y) + 10y = 135
520 - 45y + 10y = 135
-35y = -385
y = -385/-35. The negatives cancel out, leaving us with $11 for blackberries.
Now we can substitute that value into James’s equation.
x + 9(11) = 104
x = 104 - 99
x = $5
Final answer: Blueberry pies cost $5, blackberry pies cost $11.
Answer:
Enter a problem...
Algebra Examples
Popular Problems Algebra Solve by Substitution 3x-4y=9 , -3x+2y=9
3
x
−
4
y
=
9
,
−
3
x
+
2
y
=
9
Solve for
x
in the first equation.
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x
=
3
+
4
y
3
−
3
x
+
2
y
=
9
Replace all occurrences of
x
in
−
3
x
+
2
y
=
9
with
3
+
4
y
3
.
x
=
3
+
4
y
3
−
3
(
3
+
4
y
3
)
+
2
y
=
9
Simplify
−
3
(
3
+
4
y
3
)
+
2
y
.
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x
=
3
+
4
y
3
−
9
−
2
y
=
9
Solve for
y
in the second equation.
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Move all terms not containing
y
to the right side of the equation.
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x
=
3
+
4
y
3
−
2
y
=
18
Divide each term by
−
2
and simplify.
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x
=
3
+
4
y
3
y
=
−
9
Replace all occurrences of
y
in
x
=
3
+
4
y
3
with
−
9
.
x
=
3
+
4
(
−
9
)
3
y
=
−
9
Simplify
3
+
4
(
−
9
)
3
.
Tap for more steps...
x
=
−
9
y
=
−
9
The solution to the system of equations can be represented as a point.
(
−
9
,
−
9
)
The result can be shown in multiple forms.
Point Form:
(
−
9
,
−
9
)
Equation Form:
x
=
−
9
,
y
=
−
9
image of graph
you multiply 35 to 72 to get 2520 and then multiply 23 to 94=2139 add both of the answers to get 4659
Answer:
Decreased by 20%.
16 lbs is 80% of 20 lbs.
Step-by-step explanation:
y × 20 = 16 × 100
20y = 1600
20y ÷ 20 = 1600 ÷ 20
y = 80
100% - 80% = 20%
