(3ab-2a-2)-(4ab-4) find the difference

Two cars left the city for a suburb, 120 km away, at the same time. The speed of one of the cars was 20 km/hour greater than the

Virty [35]

Answer:

V1 = 60 km/h

V2 = 40 Km/h

Step-by-step explanation:

The speed of an object is defined as

Speed = distance / time

Let

V1 be the speed of the faster car

V2 be the speed of the other car

t1 the time it took for the first car to arrive

t2 the time it took for the second car to arrive

d1 the distance traveled by first car

d2 the distance traveled by second car

We know thanks to the problem that

V1 = V2 + 20 Km/h

t1 = t2 - 1 hour

d1 = d2 = 120 Km

d1 = V1 * t1

d2 = V2* t2

V1 * t1 = V2* t2

V1* t1 = (V1 -20)*(t1 +1)

The system of equations

(V1 -20)*(t1 +1) = 120

V1 * t1 = 120

120 + (120/t1) -20*t1 = 140

(120/t1) -20*t1 = 20

Which gives,

t1 = 2

This means

V1 = 60 km/h

V2 = V1 - 20 Km/h = 40 Km/h

6 0

3 years ago

The perimeter of a parallelogram is 76 inches and 1 side measures 14 inches of it can be determined what are the lengths in inch

nydimaria [60]

The dimension of the parallelogram ABCD will be 14 inches, 48 inches, 14 inches and 48 inches.

<h3>What is a parallelogram?</h3>

It is a polygon with four sides. The total interior angle is 360 degrees. A parallelogram's opposite sides are parallel and equal.

The perimeter of a parallelogram is 76 inches.0

And one side measure is 14 inches.

Then the rest of the sides will be

We know that opposite sides are prallel and equal.

Let ABCD is a parallelogram.

AB = CD = 14 inches

BC = AD = x

Then the value of x will be

We know

P = 2(AB + BC)

76 = 2(14 + x)

x = 48

More about the parallelogram link is given below.

brainly.com/question/1563728

#SPJ1

5 0

2 years ago

Diego is solving the equation x^2-12x = 21

uysha [10]

Answer:

The solutions to the quadratic equations will be:

$x=\sqrt{57}+6,\:x=-\sqrt{57}+6$

Step-by-step explanation:

Given the expression

$x^2-12x\:=\:21$

Let us solve the equation by completing the square

$x^2-12x\:=\:21$

Add (-6)² to both sides

$x^2-12x+\left(-6\right)^2=21+\left(-6\right)^2$

simplify

$x^2-12x+\left(-6\right)^2=57$

Apply perfect square formula: (a-b)² = a²-2ab+b²

i.e.

$x^2-12x+\left(-6\right)^2=\left(x-6\right)^2$

so the expression becomes

$\left(x-6\right)^2=57$

$\mathrm{For\:}f^2\left(x\right)=a\mathrm{\:the\:solutions\:are\:}f\left(x\right)=\sqrt{a},\:-\sqrt{a}$

solve

$x-6=\sqrt{57}$

add 6 to both sides

$x-6+6=\sqrt{57}+6$

Simplify

$x=\sqrt{57}+6$

also solving

$x-6=-\sqrt{57}$

add 6 to both sides

$x-6+6=-\sqrt{57}+6$

Simplify

$x=-\sqrt{57}+6$

Therefore, the solutions to the quadratic equation will be:

$x=\sqrt{57}+6,\:x=-\sqrt{57}+6$

5 0

3 years ago

Pedro bought lb of red sand and lb of brown sand to refill his sand box. Both types of sand cost $4.60 a pound. How much did Ped

Doss [256]

If we know that Pedro bought 1 $\frac{1}{4}$ pounds of red sand, and 5 $\frac{1}{2}$ pounds of brown sand, and they both cost $4.60, then we just have to add the individual amounts of sand, since they cost the same.

$1 \frac{1}{4} + 5 \frac{1}{2} = 6 \frac{3}{4}$

So Pedro bought $6 \frac{3}{4}$ lbs of sand overall. Now, we just need to multiply the cost per pound by the total amount of sand he bought.

$6 \frac{3}{4} * 4.6 = 31.05$

Pedro spent $31.05 on sand, which is answer choice B.
Hope that helped =)

4 0

4 years ago

Read 2 more answers

What is the first step in isolating the variable in this equation?

VLD [36.1K]

It’s either subtract 75 from both sides or divide both sides by 1/2 but I’m pretty sure it’s subtract 75 from both sides

6 0

3 years ago

Read 2 more answers