Answer:
The value of a is 10.
Step-by-step explanation:
We are given with the following pair of the linear system of equations below;
and
.
Also, the solution is given as (a, -1).
To find the value of 'a', we have to substitute the solution in the equation because it is stated that (a, -1) is the solution of the given two equations.
So, the x coordinate value of the solution is a and the y coordinate value of the solution is (-1).
First, taking the equation;
Put the value of x = a and y = -1;
(-1) = -(a) + 9
a = 9 + 1 = 10
Now, taking the second equation;

Put the value of x = a and y = -1;

0.5a = 6 - 1
0.5a = 5
a = 10
Since we get the value of a = 10 from the equations, so the value of a is 10.
Answer: the height in inches, of the pile after 3 weeks is 34 11/12 inches
Step-by-step explanation:
Each consecutive week for the next 5 weeks the height of pile increase by 8 7/12 inches. Converting 8 7/12 inches to improper fraction, it becomes 103/12 inches. The height is increasing in an arithmetic progression. The formula for determining the nth term of an arithmetic sequence is expressed as
Tn = a + (n - 1)d
Where
a represents the first term of the sequence.
d represents the common difference.
n represents the number of terms in the sequence.
From the information given,
a = 17 3/4= 71/4 inches
d = 103/12 inches
n = 3 weeks
the height in inches, of the pile after 3 weeks, T3. Therefore,
T3 = 71/4 + (3 - 1)103/12
T3 = 71/4 + 2 × 103/12 = 71/4 + 103/6
T3 = 419/12 inches = 34 11/12 inches
Here’s the correct answer and how I got it :)
The trick question is that you can’t effect an unknown value because you don’t know what number it is, it has to be a known value, there is nothing that you can do to figure it out, so it’s unknown and cannot be effected.
Do you think than i ve understood it right
3x+9=30
3x=21
x = 21/3 = 7
x = 7
hope helped