Answer: 46
Step-by-step explanation:
You can simplify this using PEMDAS:
Parentheses
Exponents
Multiplication/division
Addition/subtraction
Move through the steps in that order.
In this case, the first two steps are absent, so multiply first:
20 - 16 + 42
Then, add and subtract:
46.
Answer:
136 cm²
Step-by-step explanation:
Surface area = 2(lw+wh+hl)
l = 7
w = 2
h = 6
so,
2(7×2+2×6+7×6)
= 136 cm²
<h3>hello!</h3>
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Let's simplify the expression:-

Multiply 3 times 1 and 1 times 2:-

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<h3>note:-</h3>
Hope everything is clear; if you need any clarification/explanation, kindly let me know, and I'll comment and/or edit my answer :)
Angle D is 180° -75° -45° = 60°. Drawing altitude MX to segment DN divides the triangle into ΔMDX, a 30°-60°-90° triangle, and ΔMNX, a 45°-45°-90° triangle. We know the side ratios of such triangles (shortest-to-longest) are ...
... 30-60-90: 1 : √3 : 2
... 45-45-90: 1 : 1 : √2
The long side of ΔMDX is 10√3, so the other two sides are
... MX = MD(√3/2) = 15
... DX = MD(1/2) = 5√3
The short side of ΔMNX is MX = 15, so the other two sides are
... NX = MX(1) = 15
... MN = MX(√2) = 15√2
Then the perimeter of ΔDMN is ...
... P = DM + MN + NX + XD
... P = 10√3 +15√2 + 15 + 5√3
... P = 15√3 +15√2 +15 . . . . perimeter of ΔDMN