math help??

Question

1.The perimeter of a rectangle with the area of 60cm2 is 34cm. Find the sides of the rectangle.

can you please write the formula

thanks

Answer 1

ok, so Area=length*width, A=l*w
Perimeter=len+len+wid+wid=2l+2w

P=2l+2w=34
A=l*w=60

since l*w=60, then l=60/w

P=2l+2w=34
P=2(60/w)+2w=34
P=120/w+2w=34
P=120+2w^2=34w (I multiply by w)
P=2w^2-34w+120

then you do the factoring thing

P=(w-5)*(2w-24) to equal 2w^2-34w+120

(w-5)=0
w=5
(2w-24)=0
w=12
so, w=5 and w=12

The sides of the rectangle are 5cm by 12cm

Answer 2

Let the sides be x and y

xy = 60.......A
2(x + y) = 34......B

Consider B
2(x + y) = 34
x + y = 17
y = 17-x......C

Substitute C in A
xy = 60
x(17 - x) = 60
17x - x^2 = 60
-x^2 + 17x - 60 = 0
-x^2 + 5x + 12x - 60 = 0
-x(x - 5) + 12(x - 5) = 0
(12 - x)(x - 5) = 0
x = 5, 12
y = 5,12

When x is 5, y is 12 and vice versa.
In general the measures of the sides are 12cm and 5cm

Answer 3

The area is the length times the width, say a x b=60
The perimeter is twice the width plus twice the height, say 2a + 2b=34

This gives you two equations.

Now you know that a+60/b so substitute this into the other equation, forma a quadratic and solve it yourself.

Answer 4

first of all in which grade r u? lol just asking...well here's the formula:i m not sure may be it is rite ....
area of rectangular =34cm
perimeter of rectangular=60cm2
sides of the rectangle=?

s=area multiply by perimeter
putting the values
s= 34cm multipy by 60cm2
side= 2040cm3

Answer 5

x*y = 60
2(x + y) = 34
x + y = 17
y = 17 - x
17x - x^2 = 60
x^2 - 17x + 60 = 0
x = (17 ± √(289 - 240))/2
x = (17 ± √49)/2
x = (17 ± 7)/2
x = 5,12
y = 12,5
The rectangle is 5 cm x 12 cm.

Answer 6

Area of tri = l * b
Perimeter = 2(l +b)

You can find both with 2 eqns.

Answer 7

w + h = 17
w * h = 60

w * (17 - w) = 60
w^2 -17W + 60 = 0