I have the answer attached.
Substitute 1 for x in each of your equations.
f(x)=7-3x
which is
f(1)=7-3(1)
=3
Do the same for g(x)
g(x)=3x-7
which is
g(1)=3(1)-7
=-4
Then subtract g(x) from f(x):
3-(-4)
=7
:)
Answer:
other person is correct
Step-by-step explanation:
Answer:
11. 78
12. 4x² - 3x - 1
Step-by-step explanation:
11. Sum of n whole numbers = ½(n² + n)
Multiply
½*n² + ½*n
= n²/2 + n/2
To find the sum of the first 12 whole number, substitute 12 for n into the equation.
= 12²/2 + 12/2
= 144/2 + 12/2
= 72 + 6
= 78
12. Area of trapezoid = ½(a + b)*h
Where,
a = 5x - 4
b = 3x + 2
h = x + 1
Area = ½(5x - 4 + 3x + 2)*(x + 1)
Area = ½(8x - 2)*(x + 1)
Area = ½[8x(x + 1) -2(x + 1)]
= ½[8x² + 8x - 2x - 2]
Add like terms
= ½(8x² - 6x - 2)
= ½(8x²) - ½(6x) - ½(2)
= 4x² - 3x - 1
Do the ones in pararenthes first then match them and U will get the answer
