помогите решить уравненияd+1/5=4/7+3/7f+4/5=4/7+3/7b+2/5=4/7+3/7

<span>d+1/5=4/7+3/7</span>

<span>д+1/5=7/7</span>

<span>д=1-1/5</span>

<span>д=4/5</span>

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</span>

<span><span>f+4/5=4/7+3/7</span></span>

<span><span>f+4/5=7/7</span></span>

<span><span>f=1-4/5</span></span>

<span><span>f=1/5</span></span>

<span><span>
</span></span>

<span><span><span>b+2/5=4/7+3/7</span></span></span>

<span><span><span>b+2/5=7/7</span></span></span>

<span><span><span>b=1-2/5</span></span></span>

<span><span><span>b=3/5</span></span></span>