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2 years ago

Can someone help me with these questions and show work please and thank you

Mathematics

1 answer:

attashe74 [19]2 years ago

6 0

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

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Solve the following word problems using a system of equations. The sum of two numbers is 36. One number is two more than the oth

juin [17]

Answer:

24,12

Step-by-step explanation:

suppose,

x+y=36

x=2y

2y+y=36

y=12

x=24

4 0

2 years ago

A ball is thrown from a height of 40 meters with an initial downward velocity of 5 m/s

arsen [322]

0=40-10t-5t^2

t^2+2t-8=0

(t+4)(t-2)=0

t=-4 (not a solution) or t=2

Answer: after 2 seconds

7 0

2 years ago

Yoo someone help asaapp!

Zigmanuir [339]

Answer:

A 76

Step-by-step explanation:

7x+8+7x-2+5x+16+110=360

19x+132=360

19x=228

x=12

∠E=5(12)+16

=76

4 0

2 years ago

Read 2 more answers

The diagram below shows the rectangle PLUM.

Illusion [34]

Answer:

Area of rectangle PLUM = 75.00 square units

Step-by-step explanation:

Since diagonal of rectangle divides the rectangle into two equal triangles,

Therefore, area of the rectangle PLUM = 2× area of triangle PLM

By the mean proportional theorem,

In ΔPLM,

AP² = AM × AL

6² = AM × 8

AM = $\frac{36}{8}$

AM = 4.5 units

Area of PLM = $\frac{1}{2}(\text{Base})(\text{height})$

= $\frac{1}{2}(ML)(AP)$

= $\frac{1}{2}(8 + 4.5)(6)$

= 12.5 × 3

= 37.5 units²

Now area of rectangle PLUM = 2×37.5 = 75 units²

Therefore, area of the rectangle is 75.00 square units.

3 0

2 years ago

1) Cathy borrows $3280 at 0.3% simple interest per month. When Cathy pays the loan back 9 years later, what is the total amount

aksik [14]

Answer:

Step-by-step explanation:

we calculate how much 0.3% is from 3280

y=3280*0.3/100=9.84$

months in 9y

12*9=108

the interest of 9y

108y=1062.72$

the sum of interest + the money borrowed

1062.72+3280=4342.72$

6 0

2 years ago

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