The length of a rectangular photo is 1 centimeter less than three times its width. If the area of the photo is 102 square centimeters, find the length and width of the photo.

The length is

and the width is

(Type whole numbers.)

Answers:

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How to get those answers:

Let w be the unknown width in centimeters. This variable is some positive real number. This means w > 0 which will be useful later.

The length is "1 cm less than 3 times its width" and it tells us the length is defined by the expression 3w-1. Whatever w is, we triple it to get 3w and then subtract 1 to get the final length.

Multiply the length and width to get the area 102

length*width = area

(3w-1)*w = 102

3w^2-w = 102

3w^2-w-102 = 0

We could guess and check our way to factoring this, but that's not very efficient. The quadratic formula is the better option. It may seem a bit messy, but it's a more direct path that doesn't involve guessing.

We ignore the second solution (w = -5.667 approximately) because we stated earlier that w > 0. In other words, a negative length does not make sense, so that's why we ignore it.

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If w = 6 cm is the width, then 3w-1 = 3*6-1 = 18-1 = 17 cm is the length.

Note that length*width = 17*6 = 102 which is the proper area we want. This confirms the answers.

given that triangle abc is transformed two times to get triangle

a"b"c"

first abc is transformed in to a'b'c' as follows:

the coordinates of a are (1,-1) and transformed into a'(-1,1)

similarly b (4,-2) became b'(-4,2) and

c(7,-2) became c'(-7,2)

i.e. (x,y) becomes (-x,-y)

this is nothing but reflection about a point here origin.

thus first transformation is reflection on the origin.

next is exactly shifting 3 units down

source:

13

step-by-step explanation:

169-1=168

168-3=165

165-5=160

160-7=153

153-9=144

144-11=133

133-13=120

120-15=105

105-17=88

88-19=69

69-21=48

48-23=25

25-25=0

since it took 13times to completely subtract it hence its square root is 13