Answer:
There are infinitely many solutions.
Step-by-step explanation:
3x + 2y = 7
-9x - 6y = -21
Now multiply the first equation by 3
3 × 3x + 2y = 7 ➡ 9x + 6y = 21 Now subtract second equation from first equation
9x + 6y - 9x - 6y = 21 - 21
0 = 0
The equation has infinitely many solutions meaning whatever value you write instead of x and y there will be solution.
The expression 4x^2 represents - (4)(x)(x)
Answer:
x = 45
Step-by-step explanation:
Corresponding sides of similar triangles will be in same ratio.
Cross multiply
x*28 = 20*(x+18) {Use distributive method}
28x = 20x + 360
28x - 20x = 360
8x = 360
x = 360/8
x = 45
Answer:
see explanation
Step-by-step explanation:
The circumference (C) is calculated as
C = πd ← d is the diameter
diameter = 2 × 9 = 18 in ( twice the top diameter ), thus
C = 18π in ← exact value ≈ 56.55 in ( to 2 dec. places )
Answer:
4 hours
Step-by-step explanation:
The amount remaining at the end of each hour is 0.85 of the amount at the start of the hour. You want to find the exponent such that ...
... 0.85^x = 0.5 . . . . . x = the number of hours until half is left
... x·log(0.85) = log(0.5) . . . . . take the log to turn it to a linear equation
... x = log(0.5)/log(0.85) ≈ 4.265024
Rounded to the nearest hour, x = 4.
