Amber tried to evaluate an expression step by step. \quad\begin{aligned} &-3-(-5)+4 \\ =&-3+5+4&\green{\text{Step } 1} \\ \\ =&-3+9&\blue{\text{Step } 2} \\ \\ =&\:\:\:6&\purple{\text{Ste p } 3} \\ \\ \end{aligned} = = = −3−(−5)+4 −3+5+4 −3+9 6 Step 1 Step 2 Step 3 Find Amber's mistake. Choose 1

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Step-by-step explanation:

Amber should’ve added -3 and 5 first instead of adding 5 and 4 because if there are multiple terms with addition and subtraction/multiplication and division, the one that is first should be evaluated first  

according to the triangle sum theorem, all the angles in a triangle must add up to 180 degrees. if we know one angle is already 90, we do 180-90=90. the other 2 angles must add up to 90, exactly.

step-by-step explanation: