Dave tried to evaluate 55 – 15 + 20 step-by-step. 55 - 15 + 20

Step 1: =40 + 20

Step 2: = 20

Find Dave’s mistake

Choose 1

A: step 1
B: step 2
C: Dave did not make a mistake

Step 2

Step-by-step explanation:

In step 2 the expression was 40+20 which would have been 60 but he might have thought addition sign was subtraction so he did 40-20 which is 20 so he is wrong made mistake in step 2

x

step-by-step explanation:

geometry: triangles

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lessons

answers archive

call the larger triangle abc

then the smaller triangle cde is similar to abc (all angles are equal, aaa).  

ab is the side that is 36, and we wish to find de, the side corresponding to ab

area_cde = area_abc - area_cde --> area_abc / area_cde = 2

let x=length of de

ratio of areas = (ratio of sides)^2

+2+=+%2836%2fx%29%5e2+

+2+=+1296%2fx%5e2+

++x%5e2+=+1296%2f2+=+648+

25.45584