Answer:
1.
-3x + 8y = -5
6x + 2y = -8
Set the equations to a common variable.
-3x + 8y = -5 → 8y = 3x - 5 → y = 3/8x - 5/8
6x + 2y = -8 → 2y = -6x - 8 → y = -3x - 4
Set the equations equal to each other.
3/8x - 5/8 = -3x - 4
Combine like terms.
3x + 3/8x = -4 + 5/8
3.375x = -3.375
Divide by 3.375
x = -1
Plug x back in to find y.
-3x + 8y = -5
-3(-1) + 8y = -5
3 + 8y = -5
8y = -8
y = -1
answer: (-1, -1)
2.
3x + 2y = -16
-3x - 8y = 46
Set the equations to a common variable.
3x + 2y = -16 → 2y = -3x - 16 → y = -3/2x - 8
-3x - 8y = 46 → -8y = 3x + 46 → y = -3/8x - 23/4
Set the equations equal to each other.
-3/2x - 8 = -3/8x - 23/4
Combine like terms.
-9/8x = 9/4
or
-1.125x = 2.25
Divide by -1.125
x = -2
Plug x back in to find y.
3(-2) + 2y = -16
-6 + 2y = -16
2y = -10
y = -5
answer: (-2, -5)
Answer:
7 mph
Step-by-step explanation:
If b is the rate of the boat, and s is the rate of the stream, then:
b − s = 4
b + s = 10
Solve the system of equations with substitution or elimination. Using elimination, add the equations together:
2b = 14
b = 7
The boat's rate is 7 mph.
Answer:
24.7
Step-by-step explanation:
.38(65)
Answer:
no 6 hours
Step-by-step explanation:
no it would be 6 hours
25% = 7.5 hours
5% = 1.5 hours
7.5 - 1.5 = 6 hours
∠A, ∠B, ∠C - interior angles of a triangle.
∠A 1 , ∠B 1 , ∠C 1 - exterior angles of a triangle.
∠A + ∠B + ∠C = 180°
∠A + ∠A 1 = 180°
Therefore: ∠A 1 = ∠B + ∠C ( two remote interior angles )
Answer:
An exterior angle of a triangle is equal to the sum of the two remote interior angles.