MATHEMATICS MIDDLE SCHOOL

Solve 5r2 – 12 = 68. {±4} {±5} {±3} {±6}

Answers

Answer 1

Answer:

we are given

$5r^2-12=68$

Since, we have to solve for r

so, firstly we will isolate r terms

so, we will move 12 on right side

we can add both sides by 12

$5r^2-12+12=68+12$

$5r^2=80$

now, we can divide both sides by 5

$(5r^2)/(5) =(80)/(5)$

$r^2=16$

now, we can take sqrt both sides

and we get

$r=4 , r=-4$

so,

{±4}..........Answer

Related Questions

N+-6=11 that's what I need to know
Find the area of the triangle
Which number is between 0.5 and 8/9?A) 7/24B) 22/24C) 25/36D) 1/3
In the figure below, Sin 62 degrees - 17/c. Based on the figure, which of the following equations is also true ?A. Cos 62 degrees = 17/cB. Tan 62 degrees = c/17C. Cos 28 degrees = 17/cD. Sin 28 degrees = c/17
Mrs. Jacobs drove at a speed of 60 km/h to her mother's house 120 km away. She picked up a box of photos and drove back home at 40 km/h.Mrs. Jacobs thought to herself, "Well, I drove 60 km/h to get there, and 40 km/h to get home. I must have averaged 50 km/h for the whole trip." Do you agree with Mrs. Jacob's conclusion? Why or why not? Can someone please help me with the above problem? Thank you!

One tank is filling at a rate of 5/8 gallon per 7/10 hour. A second tank is filling at a rate of 5/9 gallon per 2/3 hour. Which tank is filling faster? Why?

Answers

Compare unit rates. The first one is filling at the rate of (5/8 gal) / (42 minutes) = 0.01488 gal/min (rounded). The second one fills at the rate of (5/9 gal) / (40 min) = 0.0139 gal/min (rounded). The first unit rate is greater than the second one. The first one is taking on fluid faster, but we can't say anything about "filling", because we don't know how much each tank holds, or how much may have already been in one or the other before all of this filling and running and pouring started .... I gotta go.

7/10 of an hour is 42 minutes and 2/3 of an hour is 40 minutes. It is the first tank because the other filling at 5/9 gallon for 20 minutes compared to the first tank filling at 5/8 gallon for 8 minutes.
I HOPE THIS HELPS!!!

A ball is thrown straight up in the air from a height of 6 feet at a speed of 80 feet per second. The height of the ball in feet is given by -16t^2+80t+6 where t is the time in seconds. What is the height of the ball after 3 seconds?

Answers

Substitute 3 for t in the formula for height:

$-16t^2+80t+6=-16(3)^2+80(3)+6=-144+240+6=102$

The height of the ball after 3 seconds is 102 feet.

7 less than 3 times a number m

Answers

3x-7 is the answer...

Answer:

3x-7

Step-by-step explanation:

Pls help! if f(x) = 4x^2+6/2 and g(c) = 3/2x^2+3, find f(x) X g(x)

Answers

f(x) = (4x²+6)/2 and g(x) = 3/(2x²+3)

f(x)*g(x) = (4x²+6)/2 * 3/(2x²+3) = 2(2x²+3)/2 * 3/(2x²+3) = (2x²+3) * 3/(2x²+3) =3

Answer is D.3

A cooking club has 10 members. how many ways can they select a president and vice president from among the members?A. 180
B. 20
C. 100
D. 90

Answers

There are 10 possible ways to select a president from the club, because their are 10 available members to choose from.

After a president is chosen, their are 9 possible ways to select a vice president, because one of the members will already have the position of president, so they can't be vice president (10-1=9)

Now we just multiply to possibilities of presidents by the possibilities of vice-presidents.

president*vicepresident=
10*9=90

Answer= D. 90

Lauren brings brownies to class one day. She gives 3/5 of them to her friends Gareth Tammy and Camilla. If she gave them 21 brownies, how many did she bring to class?PLEASE HELP ME!!!!