Whakaoti i te {l}{(a-d)+a+(a+d)=120}{4(a-d)+5=a+d}

$$\left\{ \begin{array} { l } { ( a - d ) + a + ( a + d ) = 120 } \\ { 4 ( a - d ) + 5 = a + d } \end{array} \right.$$

Whakaoti mō a, d

$$a=40$$

$$d=25$$

Ngā Upane Otinga

Whakaarohia te whārite tuatahi. Pahekotia te a me a, ka 2a.

$$2a-d+a+d=120$$

Pahekotia te 2a me a, ka 3a.

$$3a-d+d=120$$

Pahekotia te -d me d, ka 0.

$$3a=120$$

Whakawehea ngā taha e rua ki te 3.

$$a=\frac{120}{3}$$

Whakawehea te 120 ki te 3, kia riro ko 40.

$$a=40$$

Whakaarohia te whārite tuarua. Me kōkuhu ngā uara tāupe mōhiotia ki te whārite.

$$4\left(40-d\right)+5=40+d$$

Whakamahia te āhuatanga tohatoha hei whakarea te 4 ki te 40-d.

$$160-4d+5=40+d$$

Tāpirihia te 160 ki te 5, ka 165.

$$165-4d=40+d$$

Tangohia te d mai i ngā taha e rua.

$$165-4d-d=40$$

Pahekotia te -4d me -d, ka -5d.

$$165-5d=40$$

Tangohia te 165 mai i ngā taha e rua.

$$-5d=40-165$$

Tangohia te 165 i te 40, ka -125.

$$-5d=-125$$

Whakawehea ngā taha e rua ki te -5.

$$d=\frac{-125}{-5}$$

Whakawehea te -125 ki te -5, kia riro ko 25.

$$d=25$$

Kua oti te pūnaha te whakatau.

$$a=40 d=25$$