Answer:
x=5, y=-3
Step-by-step explanation:
we can find the answer by plugging in x=3y+14 to the second equation
5(3y+14)-2y=31
simplify
15y+70-2y=31
13y=-39
y=-3
now, plug in this to the initial equation x=3y+14
x=3(-3)+14
x=-9+14
x=5
Step-by-step explanation:
the area of a triangle
baseline × height / 2
in our case
baseline × height / 2 = 60 in²
height = 6×baseline - 16
baseline × (6×baseline - 16) / 2 = 60
baseline × (3×baseline - 8) = 60
3×baseline² - 8×baseline = 60
baseline = x
3x² - 8x - 60 = 0
general solution to a quadratic equation is
x = (-b ± sqrt(b² - 4ac))/(2a)
in our case
a = 3
b = -8
c = -60
x = (8 ± sqrt(64 - 4×3×-60))/(2×3) =
= (8 ± sqrt(64 + 720))/6 = (8 ± sqrt(784))/6 =
= (8 ± 28)/6
x1 = (8 + 28)/6 = 36/6 = 6
x2 = (8 - 28)/6 = -20/6 = -10/3
x2 as a negative number is not a valid solution for a length in a geometric shape.
so, x = 6 in is our solution for the baseline.
height = 6x - 16 = 6×6 - 16 = 36 - 16 = 20 in
base = 6 in
Answer:
C
Step-by-step explanation:
Using Pythagoras' identity to determine if the triangle is right
The square of the longest side should equal the sum of the squares on the other 2 sides, that is
QS² = RS² + QR² = 8² + 5² = 64 + 25 = 89 ( take the square root of both sides )
QS = 
Δ QRS is not right as QS would have to be 
Answer:

Step-by-step explanation:
Let the number be x
Subtract 1/2 from x = (x - 1/2)
Multiply 1/2 to the result = 1/2(x - 1/2)
The result is 1/8
That is,
