Answer:
Step-by-step explanation:
Given the expression (x+11)(2x+3)
We want to expand it and write equivalent expression
Generally if we want to expand an expression we will take one of the expression in one bracket and multiply with the other bracket and then take the other expression and multiply it with the other
E.g, (a+b) × (c + d)
Then, we take a × (c+d) and also b × (c+d)
We can do it the other way round too and it will give the same results.
So, applying this to the given expression
(x+11)(2x+3)
x(2x+3) + 11(2x+3)
2x² + 3x + 22x + 33
2x² + 25x + 33
Then, the equivalent expression is 2x² + 25x + 33
(x + 11)(2x + 3) = 2x² + 25x + 33
Part A.
The trip starts at 8am which corresponds to 0 hrs, point (0hr, 0mi)
2hrs later it's 10am. .point (2hr, 140mi)
The average speed is the slope between 0 and 2 hrs. Remember the slope formula m = Δy/Δx
m = (140 - 0) / (2 - 0)
m = 70 mph
Part B. Average speed from 11am - 2pm
11am is point (3hr, 140mi)
2pm is point (6hr, 300mi)
As you can see from the graph, the speed or slope changes at 1pm (5,260). You Can just use the start and end points.
m = (300-140) / (6-3)
m = 160/3
53.3 mph
* It comes out the same solution as if you average the two different slopes. 2hrs at 60mph + 1 hr at 40mph = (120 + 40)/3 = 160/3
Part C. Total average speed = total distance / total time driving
He went 70 mph for 2 hrs
stopped for an hour (slope is zero, no speed)
60 mph for 2hrs
40mph for 1 hr
300mi /5hr = 60mph
Part D. No Question....
Answer:
A
Step-by-step explanation:
because when you multiply 3x3 (the base) times 18(the height) you get= 162
2x2-5x-18=0
Two solutions were found :
x = -2
x = 9/2 = 4.500
Step by step solution :
Step 1 :
Equation at the end of step 1 :
(2x2 - 5x) - 18 = 0
Step 2 :
Trying to factor by splitting the middle term
2.1 Factoring 2x2-5x-18
The first term is, 2x2 its coefficient is 2 .
The middle term is, -5x its coefficient is -5 .
The last term, "the constant", is -18
Step-1 : Multiply the coefficient of the first term by the constant 2 • -18 = -36
Step-2 : Find two factors of -36 whose sum equals the coefficient of the middle term, which is -5 .
-36 + 1 = -35
-18 + 2 = -16
-12 + 3 = -9
-9 + 4 = -5 That's it
Step-3 : Rewrite the polynomial splitting the middle term using the two factors found in step 2 above, -9 and 4
2x2 - 9x + 4x - 18
Step-4 : Add up the first 2 terms, pulling out like factors :
x • (2x-9)
Add up the last 2 terms, pulling out common factors :
2 • (2x-9)
Step-5 : Add up the four terms of step 4 :
(x+2) • (2x-9)
Which is the desired factorization
Equation at the end of step 2 :
(2x - 9) • (x + 2) = 0
Step 3 :
Theory - Roots of a product :
3.1 A product of several terms equals zero.
When a product of two or more terms equals zero, then at least one of the terms must be zero.
We shall now solve each term = 0 separately
In other words, we are going to solve as many equations as there are terms in the product
Any solution of term = 0 solves product = 0 as well.
