The area of the pentagon is 140
Solve either equation for either variable. Since the second one has y on its own, the easiest choice is to solve that for y.
-5x + y = 13 ⇒ y = 5x + 13
Now substitute this into the other equation to eliminate y and rewrite it entirely in terms of x :
-3x + 3y = 3 ⇒ -3x + 3 (5x + 13) = 3
Simplify and solve for x :
-3x + 15x + 39 = 3
12x = -36
x = -3
Substitute this into either original equation to solve for y. Plugging x = -3 into the first equation would give
-3 (-3) + 3y = 3
9 + 3y = 3
3y = -6
y = -2
So the solution to the system of equations is (x, y) = (-3, -2).
Cost of items = $23.45
Tax = 8% of $23.45 = 0.08*23.45 = $1.88
Tip = 20% of $23.45 = 0.2*23.45 = $4.69
Total cost = 23.45 + 1.88 + 4.69 = 30.02
Answer: $30.02
The equation: 6r-3=45
6r=48
Answer: r=8
Answer: C= -10
Step-by-step explanation: First step: simplify both sides of the equation
3c−2(c+10)=7c−5(c+2)
3c+(−2)(c)+(−2)(10)=7c+(−5)(c)+(−5)(2) (Distribute)
3c+−2c+−20=7c+−5c+−10
(3c+−2c)+(−20)=(7c+−5c)+(−10) (Combine Like Terms)
c + -20 = 2c - 10
c - 20 = 2c - 10
Step 2: Subtract 2c from both sides
c - 20 - 2c = 2c -10 - 2c
−c−20=−10
Step 3: Add 20 to both sides
−c−20+20=−10+20
−c=10
Step 4: Divide both sides by -1
-c/-1 = 10/-1
C=-10
