Hey there :)
We have two equations:
3a + 2b = 7
2a + 2b = 9
We need to solve simultaneously to find the values of a and b
eq.1 3a + 2b = 7
eq.2 ( 2a + 2b = 9 ) x -1 ) multiply by -1 to cancel 2b
3a + 2b = 7
- 2a - 2b = -9 ( Add both together )
-------------------
a = - 2 Substitute the value you found for a in a in order to find b
3( - 2 ) + 2b = 7 2( - 2 ) + 2b = 9
- 6 + 2b = 7 OR - 4 + 2b = 9
2b = 13 2b = 13
b =
b =
There is nothing to help with...
Answer:
(f+g)(x) = 13x + 3
Step-by-step explanation:
Rewrite f(x)=2x+7 and g(x)=11x-4 in columns, as follows:
f(x)=2x+7
+g(x)=11x-4
----------------
Now add each column separately.
f(x)+g(x) = (f+g)(x) ("the sum of functions f and g")
2x + 11x = 13x, and, finally, 7-4 = 3.
Therefore,
f(x)=2x+7
+g(x)=11x-4
----------------
(f+g)(x) = 13x + 3
Answer:
(A)74
Explanation:
Let her average score on the last two tests = x.
The six scores will now be: 82,78,87,73, x and x.
Since the average score for her first six chemistry tests = 78

We then solve for x.

Her average score for the last two tests is 74.